HOW TO PREVENT THE ERASER FROM BREKING
2-2

16group S, Takahashi

Y, Tamura～Abstract～
We are fed up with breaking erasers, so we want to find
how to prevent erasers from breaking. Erasers were

③ Inspection of power

moved with them changed of the angle and distance,

Power of affecting erasers were set three-stage.

power. As a result, the factor the erasers break easily is(+1.0kg, + 2.0kg, +3.0kg)

mainly power.

※Distance which erasers move (10cm)～Introduction～
1 HypothesisAngle(30 degrees)

Speed(20cm/s)were arranged.

Erasers break easiest at an angle of 90 degrees to thedesk. Also, the larger power which affect erasers, the～Result～

more easily them break. It is because, an eraser is under

Cracked➡△， broke➡○, not changed➡×a heavy load.

Angle

1st

2nd

3rd

4th

5th

30degrees

△

×

×

×

×

2 Method/Research

60degrees

△

×

×

×

△

There were a cardboard on the scale to be arranged

90degrees

○

×

×

×

×

power which affect an eraser does 300 round trips.

① Inspection of angles
Angles between a cardboard and an eraser were set
three-stage. (30 degrees, 60 degrees, 90 degrees)

Speed

1st

2nd

3rd

4th

5th

1/1s

△

×

×

×

×

2/1s

×

×

×

△

×

3/1s

×

×

×

×

×

※Distance which erasers move (10cm)
Power(+1.0kg)

Power

1st

2nd

3rd

4th

5th

Speed

(20cm/s)`+1.0kg

△

×

×

×

×

`+2.0kg

△

△

○

△

○

`+3.0kg

△

×

○

△

○

were arranged.

② Inspection of speed
Speed of moving erases were set three-stage.
(20cm/s, 40cm/s, 60cm/s)～Conclusion～・ It is easily to break erasers had no relationship※Distance which erasers move (10cm)

between angles and speed.

Power(+1.0kg)・Affected smaller power, erasers do not break.

Angle(30 degrees)・ It is easy to break for erasers is changed by awere arranged.

combination of each condition.

Prevent skirts from rolling up
2-2 group17 Miki Saito Wakako Takakusagi

Abstract
The experiment that focus on the length of the steps and the length of the rucksack string was conductedbecause skirts make me worry about rolling up in the daily lives.
The experimental result showed that the length of the rucksack string affects.

1. Introduction(1) Background
High school girls worried about skirts rolling up in thedaily lives.

<Hypothesis2>
The length of the steps made little influence on the
result.

(2) Hypothesis
1.
2.

The shorter the rucksack string, the harder it is for
skirts to roll up.
The shorter the length of the steps, the harder it isfor skirts roll up.

2. Methods/Research<Precondition>
1.
2.
3.

The rucksack weight is eight kilograms.
Inspection time is five minutes.
Used rucksack are two kinds of it.

<Hypothesis1>
1.

The length of rucksack string was tested at
0,10,20,30 centimeters.
At a tempo of 102.

2.

<Hypothesis2>
1.
2.

The length of rucksack string was standardized at
17 centimeters.
At tempos of 102 and 153.

4. Discussion
The result that the shorter the rucksack string, theharder it is for skirts to roll up showed a relationshipbetween skirts rolling up and the position of the bottomof the rucksack.

5. Reference

3. Result

広島大学総合科学部保健体育講座

山崎昌廣<Hypothesis1>

九州芸術工科大学人間工学教室

佐藤陽彦

On average, the shorter the rucksack string the harder
it is for skirts to roll up.

「総説

ヒトの歩行－歩幅，歩調，速度およびエネルギー代謝の観点から－」（www.jstage.jst.go.jp）

Cause of the skirt rolling up due to the backpack
2-2 Nakamura Mina Machida Chihiro

ResultPeople with skirts rolled up are often

seen when carrying a backpack. Therefore we
investigated the conditions under which the skirts
were difficult to roll up even when carrying a
backpack, and considered the reason.

Introduction ⅰ) Background

High school girls

3.5
The rolled up length [cm]

Abstract

3
2.5

系列
Average

2

1
系列
Data1

1.5

2
系列
Data2
3

1
15
20
25
The length of the backpack[cm]often have their skirts rolled up when they are

Figure1 Relationship between the length of thecarrying their backpacks.

backpack and the rolled up length.
The longer length of the backpack, the longer theⅱ)Purpose To clarify the reason why the skirt rolls up

length of the rolled up skirt.

ⅲ)Hypothesis a)The larger the area where the skirt
and the backpack touch, the easier it is for the skirt toroll up.
ｂ）The heavier the backpack , the easier it is for theskirt to roll up.

Methods/Research

The rolled up length[cm]and think about countermeasures.

3.5
3
2.5

系列1
Average

2

系列2
Data1

1.5

系列3
Data2

1
4
6
8
The weight of the backpack[kg]ⅰ)Equipment used

Figure2 Relationship between the weight of the
backpack and the rolled up length.

Backpack, PET bottles, Water, Major, Hemp string,

The heavier the backpack, the longer the length of theVinyl tape, Metronome.

rolled up skirt.

ⅱ）Experimental method All the experiments wereDiscussion

unified some conditions :backpack, the speed ofwalking, the time of walking, a steady stride.
①The backpack’s string was changed for the survey.
Change the length of the backpack on the skirt to15cm, 20cm and 25cm. And unify the weight of the
PET bottles to 6kg.

It is important that the backpack

is short and the weight of the backpack is light so thatthe skirt does not roll up. Since the rolled up lengthchanges even if the stride length and walking speed
are the same, it can be said that the rolled up length
may change depending on the walking posture. Of thearea where the backpack touches the back, the areathat touches the skirt is large and the greater the force②The backpack’s weight was changed for the survey.

applied from the backpack to the back, the easier it

Change the weight of the PET bottles to 4kg, 6kg andmay be for the backpack to roll up.

8kg. And unify the length of the backpack on the skirt
to 20cm.

Alarm that don’t go back to sleep
2-3 Group 1 Inada Karen Sakurai Yurika Koido Miko

Abstract
Sleep is important for people’s lives. But some people find it difficult to get up in the morning. Will the alarms we
use on a regular basis wake up properly? It can be described that somebody’s sounds tempt us into deep sleeping.
However, we cannot wake up at the time one wants to wake up. To address these problems, we developed alarmsounds whose pitch and volume are changed. And evaluated difference of the time.
twice in the high and deformed sounds was small,

1. Introduction

while the number of people who slept twice in the low(1) Purpose

sound was overwhelmingly larger than the others.

To get up firmly based on the alarm sound of the

Therefore, it can be said that the low sound is easier

iPhone.

to sleep twice than the other two.

(2) Hypothesis

In addition, figure 2 shows that loud sounds clearly do(ⅰ) Unprocessed height makes it easy to wake up.

not sleep twice, and quiet sounds tend to sleep twice.

(ⅱ) The louder the sound is, the easier it is to wakeup.

Next, look at Table 3. This shows the average of thedifference between the time when the alarm was given

２.Method／Researchand the time when it actually happened, divided into

①Examine the pitch of the sound used as adeformation.

the athletic club and the cultural club.
40②Process the deformed alarm sound with thefrequency in the table of provisional 1 to make thealarm sound of three heights.
③Ask 6 randomly selected people to actually use thesound and answer the questionnaire.

30
26.6

23.3
20

6.7

In both cases, there is a
big difference in the
low sound, and it can be

9.47

said that it is unlikely to

0
high

low

occur. However, there

Culture club

is a big difference in the

middleSports club

high-pitched sound in

3. Result

Figure3. Average time difference

The culture club.

①Deformation 2692Hz ②High 5405Hz low 1357Hz

From the above, it is presumed that medium alarms③Please show that two figures.

and loud alarms are likely to wake up.

6
4

4
2

6

5

4

5

5

4

4. Consideration

4

2

2

1

2

2

0

1

1

In all experiments, low-pitched alarms were found to
be difficult to wake up. This is probably because the

0

○

×

Figure1.Change the heightstimulation to the brain is small. Also, comparing the
Culture Department and the Athletic Department, the〇×

Figure2.Change the loudness

difference between the time when the Culture
Department wakes up and the time when they want toFigure 1 shows whether or not you slept twice bywake up is larger. Therefore, it was found that there ischanging the sound. The number of people who slept

no correlation between the alarm sound and fatigue.

③

Marimba sound and irregular④ Marimba sound and regular⑤ Bell sound and regular⑥ Metal sound and regular⑦ Metal sound and irregular
2-3 (2) Ayaka Shiobara /Chika Sugiyama/ Nanami Yamori

How to ; With the cooperation with 8 people with

Abstract

the 7 sounds, in a week as well as the provisional

Can you get up early without your family’s voice?
Can you get up within 10 minutes actually?
Maybe many people are not good at getting up early
but someday we have to wake up by ourselves.

verification ; Time you want to wake up , wake up ,ease of waking up ( 5 grades )Result ; following the graph.
（best result →redworst result →green）

So we researched the best sound to awake.

The provisional verification

numberaverageaverage evaluation

①

11.8

4

②

16

3.8

③

23.6

3

④

7

3.5

⑤

41.4

3.4

➅

27.3

3.1

⑦

11.8

3.4

Use ; 6 alarm sounds with changes in tempo , height ,on the iPhone.

How to ; the time you want to wake up , you wakeup , and the ease of waking up with the cooperationof 6 people.

Result ; “chime” and “opening” have small
difference between the time a person wants to wakeup and the time when a person waked up.

Conclusion
Find the similarities and differences between the 2

The average evaluation is higher for regularlysounds mentioned above.

flowing one.

Similarities; there is a large differences between the

There might be a causal relationship between thehighest and the lowest points of hertz (height)

ease of waking up and the relationship of being

Differences; “opening”has a constant tempo of 160 ,awakened.

while the “chime” voice is flowing irregularly.

There are individual differences in the ease of waking
up. (Health status, sleep time, etc.)

Main verification
Creating an alarm sound that always occur within an

References

error of 10 minutes.

『朝の目覚めに効果的なアラーム音は？』Use ; based on the provisional verification.

www.francebed.co.jp『目覚ましに最適な iPhone のアラーム音』① All(marimba, bell , metal)sounds andregular tempo(160)② All sounds and irregularwww.standby-media.jp『目覚めの良いスマホのアラーム音とは？』
www.itmedia.co.jp

Growing plants with less effort!
- Efficient soil using polymers -２－４

Mizuki Aihara

1. Abstract
We studied the conditions under which plants can be cultivated with less

Suzu Imaizumi

Kurumi Higuchi

5.Results・Discussion＜ｇ＞
8.0＜ｍS／㎝＞
0.80

using highly absorbent polymers and soil. As a result , it was found that thepolymer placed in the upper layer＋medium layer was most desirable because
it has the most nutrients in the soil.

2. Introduction
We have been interested in desert greening for a long time. Up closer
inspection, we found that the desert uses highly absorbent polymers.
According to the reference, the yield increased by about 1.5 times when thepolymer was in the soil. There are several possible uses of polymers, so we
decided to find out if it's really best to mix them.

3. Methods〈equipment〉
1Lbeaker×4・highly absorbent polymers・vermiculite・
plant nutrition・nutrient measuring instrument
・electronic balance〈procedure〉
32g of polymer was placed in the beaker in 140g of soil in the ①upper layer,②medium layer, ③lower layer, ④upper＋medium layer, and left for a week
to examine the state of nutrition and moisture penetration into the soil. Thechange in the amount of water was measured by checking the weight of thesoil, and the change in the nourishing content was measured by mixing waterwith the soil and measuring it with a nourishing measuring instrument. (※The upper and lower polymers were spread uniformly, and the polymers insidewere divided into multiple and made into dumplings. )mediumaaeffort, focusing on moisture and nourishing. We studied optimum structure by

6.0

0.60

4.0

0.40

2.0

b

b

0.20

0.0

0.00
① ② ③ ④moisture①②③

nourishing④＜About moisture＞
This time, the error range was large, and there was no significant
difference between each group. According to the reference, thedifference seems to be clear when the experiment is done such a long
period as plants actually grow, so it is thought that the reason forthe difference was that the experimental period was as short as one
week. In addition, since the measured moisture content value wassmall, it is possible that the weight of the soil that could not becompletely removed from the polymer has a large influence. So it
may be due to experimental methods.
＜About nourishing＞
The nourishing experiment obtained the result with little
standard error, which was different from moisture. Upper layer(type① ) and upper +medium layer(type ④ ) were significantly better
results. There was no significant difference between them, but since
the average value is high, we choose upper+medium layer(type④). It
can be theoretically proved from the point that there is a lot ofcontact area with the soil.

6. Future outlook
This time, we obtained the results on nourishing, but there were
deficiencies in the experiment on moisture, and we did not get thecorrect result. So we would like to modify the method ofexperimentation on moisture next time.

4. Hypothesis
Since the polymer does not touch the outside air, the amount of evaporationis small and the lower layer (type④)subjected to the gravity of the soil on its
top must have the best condition in moisture and nutrient penetration.

７.Reference
https://www.jstage.jst.go.jp/article/jjfs/100/6/100_229/_pdf/-char/ja
日本家政学会誌 vol,40 No.8 721~724(1989)

２－４－３ Kamei Haruka・Kasai Yuki・Yamada Hiromu

Glycerin

Water

Total

1 time

0g

500g

500g

2nd time

250g

250g

500g

st

We tried various ways to make PRINCE

RUPERT’S DROP, but it all failed. So weHot(60℃)

decided to research nature of glass to find out

3rd time

0g

500g

500g

the cause of the experiment.

4th time

250g

250g

500g

5 time

500g

1500g

2000g

th

・It melted the empty glass stick and brokethrough the air inside.
・The water was not so high that the melted
glass had broken before it chill.

・There was a lot of melted glass.
⑴ Purpose① To

reproduce

・We failed even if we changed the quantity.

PRINCERUPERT’S

DROP with a high probability.
② To find out if we can reproduce themodern glass.
⑵Hypothesis

There is a success in a small amount of liquid.
→From these two，the amount of liquid is
not relevant.
・ Since the temperature was low, the airaround the glass didn’t melt.

If it’s an amorphous, then you can recreate it.
・A glass bar with no holes.
・Only Glycerin.
Change things are the proportion of water・The temperature of liquid is low.

and glycerin, water temperatures.

If we have these three conditions, we’ll succeed.

① Measure the weight and the temperature

But the fire of the glycerin is lower than theof water.
② Add Glycerin to water at the hate of themelting of glass, we need to consider the riskof fire.

decision.
③ Heat the glass stick with a hand burnerand drop of ② liquid.

https://www.bing.com/images/search
NIPPONICA

I failed five times.

How to extend the distance of the handball
Abstract

2-4 15 Hibiki Hayashi Anri Horiuchi

The handball is under-slow, and if you don’t hold the ball, put on a run-up, twist your body and throw it, you can
get a long distance.
Method①

1.Introduction

１. face the front

Purpose:To improve the record in the physical fitness
test.

2.stand at right angles to the throwing direction andthrow with rotating body.
3.turn your back in the throwing direction and

2.Tentative research

throw.

Experiment with the expectation that under-throw

Method②

Method③

will fly more than over-throw(throw 15 times each for

1.with run-up(2m)1.grab the ball and throw it

over-throw and under-throw, and compare the average

2.no run-up

2.don’t grab the ball, just put

distances)it in your hand

It turned out that the under-throw flies better than the(3) Research results

result.
average

As a consideration, it is thought that the reason why
the under-throw flew more than the over-throw isbecause of the rotation of the body.

20.8

15.3

15.82

13.83

③－１
②－１

①－２②－２③－２

under

①－１
0

HIBIKI

hibiki①－３≪Average≫
over

anri

ANRI

3.Main research(1) Hypothesis① It is good to turn your back in the throwing
direction and throw.
② It is longer distance to throw with run-up thanno run-up.
③ As for how to hold the ball, it is better to fly it
as if you put it on the ball without grasping it.
(2) Research method

5

10

15

20

4.Consideration
From the results, it was found that it is best to throw
the ball with the ball in your hand with a run-up while
twisting your body at a right angle from the throwing
direction. From this, it is considered that the initial
velocity of the ball is increased by giving momentum tothe body by the force of rotation of the body and theapproaching run, so that the flight distance is increased.

5.SummaryCriteria … stand at right angles to the throwing

・Under-throw

direction and throw the ball without grabbing it and・Right angle from the throwing direction

throw it without a run-up.

・Throw with run-up

Throw 5 times (2 people) with each method and・Throw the ball in your handcompare the averages.

These four conditions give the longest flight distance.

25

How to split one-use chopsticks in the center
2-5 Group25-2

Ino Haruka Takeuchi Kyoko

Abstract
It is difficult to split one-use chopsticks in the center. It can be described that one-use chopsticks will be split
when an equal power works both sides of them. However the way which one-use chopsticks can be split in thecenter is not known. To address these problems, we researched which power can split one-use chopsticks in thecenter, and those were split in the center when one-use chopstick’s one side is pulled and the other side is fixed.

1 Introduction

than its left side.

One-use chopsticks which we could not split in the

But it was difficult to take an equal time in order tocenter is difficult to use and make us depressed. And

split one-use chopsticks. So another experiment was

we sometimes feel dull pain when we use them.

add. It enable one-use chopsticks to be pulled by an

Therefore we decided to make a study about how toequal power accurately.

split one-use chopsticks in the center.

C ) Pull one-use chopstick’s right side and fixed its left

One-use chopsticks are split in the center when they
are pulled by an equal power on both sides. It can be
described that it is difficult to split it in the centerside at three points.

3 Result

because of our dominant hands. One-use chopsticks
are pulled by a bigger power on right side when it issplit by a person who is a right hander.

2 Methods

A

B

C

success

4

1

6

failure

16

19

14

20%

5%

30%

success

Thread was put on the point of 5cm from the end ofrate

a one-use chopstick. It was pulled vertically and straight.
There were two kinds of ways to pull the thread. 20
one-use chopsticks were split at one pattern.
(Figure 1)(Table 1)
C had the largest number of one-use chopsticks split
in the center.

4 Discussion
The result of the experiment was that C is the best
way to split one-use chopsticks in the center. This< Success><Failure>

result leads to the conclusion that one-use chopsticks
are split in the center when they are pulled by an equal
power on both sides.

A ) Pull one-use chopsticks by an equal power on bothsides. Thread was pulled a constant distance on bothsides , taking an equal time.
B ) Pull one-use chopstick’ right side by a bigger powerA projection angle of a ball to reach the longest distance
2-5 miyuki kenjyo, aoi kotani

Abstract

ResultTo measure correct numeric data, our own device was

投射角度 飛距離

It was found from the result that aused. It was examined the relationship between a20°

2192mmprojection angle of 45 degrees

35°

2246mm

40°

2738mmexperiments of angles of 20, 40, 60 and 80 degrees were45°

2780mmdone. However, there was the situation it was not easy

50°

2690mmto measure distance. So the survey was conducted at an

60°

1858mmprojection angle of a ball and distance. At first,

made the longest distance.

Table 1 .Result

angles of 35, 40, 45 and 50 degrees. In conclusion,
throwing of an angle of 45 degrees made the longest

飛距離と投射角度の関係

distance.

Introduction(１)purpose
There is strength decline among young people

飛距離（㎜）

3000
2000
1000
0
20° 35° 40°

recently. Especially, that of throwing ball is severe.
Therefore, the way throw a ball father should be spread.
(２)hypothesis
The angle of 45 degrees can make the longest

45° 50° 60°

投射角度（°）

Graph 1 .Frying distance and angle of projectoin

distance in theory.

Discussion
Methods
Our own device was used to measure the correct
numeric data. The device was made of cardboard and a
PVC pipe. A tape measure was put on the floor before
experiment. One adjusted an angle and measured theflying distance , the other projected the ball.

At a projection angle of 45 degrees, it had the longest
distance. However, there was not much difference
among the data. And there was variation in the sameangle setting. It seems to be the effect of the difference
in initial speed. Therefore, experiments focused on
initial speed should also be conducted.

Reference「ボールを遠くへ飛ばすには」（https://gakushu.shizuoka-c.ed.jp/science/ronnbunshu/062098.pdf）
Figure１.The appearnce of an experiment

The color that are recognized quickly.
2-5 Kana Otsuki

Miyuna Shibasaki

Yuina Mori

Abstract
Subjects see what are displayed on the projector and respond questions to find the color that are recognized quickly. The result of black backgroundis different from the result of white background.

1, Introduction

Countdown→Indication→Entry→Countdown→…

When we live normally, we recognize a lot of colors. For example, roadCircle:3.0s→

0.5s → 4.0s →

3.0s

→…

signs are red, blackboards are green, and chalks are white. Then, what

N&A :

3.0s

→

1.0s → 4.0s →

3,0s

→…

is the best color to recognize to see easily? If we can know the answer,

3. Result

we can use effectively our notebooks, posters, and so on.

80

2. Methods/Research

60

Colors of target:

40

0

255

255

255

0

127

0

G: 0

0

255

127

127

255

0

255

B : 0 255

0

0

255

255

127

0

40
18 14 1824
7

5

all of the colors are made of those three colors. An RGB is a value for

20

8

11 13

30
12

0

0

(Human can recognize colors in three colors: red, green, and blue, and

36

20

Red
Blue
Yellow
OrangePink
Light Blue
PurpleGreen

R : 255

28

20

Red,Blue,Yellow,Orange,Pink,Light Blue,Purple,Green

54

60

60

Red
Blue
Yellow
OrangePink
Light Blue
PurpleGreenbeen used to express a danger.

Background:Black

Background:WhiteAnd we predicted red is the best color to recognize because red has

Red

Blue

Red

Blue

Yellow

OrangeYellow

OrangePink

Light Blue

Pink

Light Blue

PurpleGreen

PurpleGreen

assigning a color, and when each color of red(R), green(G), andblue(B) is assigned by a value of 0 to 255 that the color can be
determined by a combination of values.)

Graph.1

Graph.2

Two types of background (white and black) are prepared because we

The whole of results

thought that chrome of background will have a relationship with100

experimental result.

80

72
36

25

31

43

36

35

0

Red

Blue

Yellow

OrangePink

Light Blue

PurpleGreen

Graph.3
Chart.1

4. Discussion

The slides were displayed on the projector, and we asked them to

From the finding of research, the consideration was found that red iswrite the color that left the most impression in the case of circles andthe best color to recognize in the case of the background is white, andthe one that appeared the fastest in the case of number and alphabet. A

yellow is the best color in the case of the background is black. But a

dot was set in the middle to be prevent from bias a point of view.

relationship could be seen between the result of these experiments andSpecifically, the experiment was advanced as follows.

not so much RGB as background color. So, we should use red to write
notebooks, and yellow to write blackboards.

To sprit apart one-use chopsticks evenly right and left sides
2-5 Matsuri Ubukata,Ito Osaka

Abstract
We worked on a research to sprit apart one-use chopsticks evenly right and left sides.
We checked three perspectives,direction of chopstics,holding position and whether to fix or not.
The result:sideways is better than lengthways/6cm,tip and 12cm in that order/fixation does not matter.

1.introduction

３．Result

Background:we want to have a nice meal!

The result in table1 were obtained from experiments.

Hypothesis:①having a position 6cm from the tip

tip

6cm

12cm

②hold chopsticks levelsideways fixedly

0.11550.1195

0.112③fix ones hand

lengthways fixedly

0.12950.13750.1375

sideways not fixedly

0.1415

0.096

0.157

lengthways not fixedly 0.1095

0.12850.21

2.Methods/Research・direction of chopstics
tip,6cm,12cm(figure1)

Table1・holding position

From table1,we arranged in decending

sideways(figure2) lengthways(figuer3)

and gave marks. (12,11,10,…,2,1)

・whether to fix or not

Sideways> lengthways

41point>37point

fixedly(figure4) not fixedly(figure5)

fixedly =not fixedly

39point=39point

6cm>tip>12cm

35point>26point>17point［g］

order of results

The best position was 6cm,next was tip,worst was 12cm.
Sideways was better than lengthways.
Whether fixedly or not was irrelevant.
figure1

figure2

4.Discussion
directionofchopstics

andholding

positionwasproved.But whether fixedly or not was not proved.
We thought that there were some causes.
First,there were individual differences in shape evenFigure3

figure4among the same one-use chopsticks.
Second,the number of subject was not enough.
Third,we could not judge whether equal or not by using
electronic scales.

5.Referance
Figure5
The number of subject:2
The number of one-use chopsticks:split 10 perpersoninevery verification
Compare the weight of left and right by electronic scales.
Compare on an average of 20.
We did not take into account the time to divide.

Superlife.@.webry.info
割り箸をキレイに左右均一に割る方法：古川修

~To keep the volume below 50% of normal sound~
2－5 Anon Uchida, Yukina Tomaru, Ayano Motohashi

Abstract
Even if it is a trivial problem, the sound of ball-point pens prevents us from focusing on studying. So, we considered ways to reduce thesound from the perspective of pushing and components. When UV resin is used, the normal sound was measured at 50％ or less.
Effective method was searched based on the result of this research and the cause of the sound arising from structure of ball-point pens.

1. Introduction

3. Result(1) The background of the study(1) the room soundThe sound of ball-point pens sometimes makes us

1

43,5

uncomfortable during classes. (The research by

2

47,6

cancam.jp in 2016 also found the same thing.) It might

3

43,5

be a common thing, but the sound prevents us from

4

43,5

focusing on things we should do. If it is solved, our life

5

43,5

average

44,32

is expected to be more comfortable.

subtract this average
from measured value(2) combination(2) Hypothesis
To reduce the sound…
① modify the parts of ball-point pens
② modify the way of push pens
2. Methods/Research

averagecalculation

A+B

62,7

18,38

A+B'

58,2

13,88

A+B''

56,2

11,88

A'+B

56,0

11,68

A'+B'

49,5

5,18

72% down(1) measure the volume of normal sound and the room
4. Discussion

sound(2) experimentally make parts of ball-point pen<used materials>

How to push: When cavity is covered by hand…
Parts: When UV resin is used…

・UV resin ・liquid rubber ・silicon→ the sound was reduced

・weight saved resin clay ・oyumaru(But there are some problems in functionality anddifferences between each cases.)
5. Reference「仕事中に「イラッとする音」選手権、1 位に輝いたのは無意識にやっPicture1ているアノ音！」（https://cancam.jp/archives/225570）(used materials)「タイピング音がうるさい人に教えよう！タイピング音を静かにする
ための 3 つの方法」(3) change the combination of parts and way of pushand measure the volume(https://rikunabi-yakuzaishi.jp/article/ore/typing/)

2-5 33-③ Chika Nakagawa

Riho Hashiba

Abstract
The noise of ballpoint pen knock is sometimes noisy for us. It can be described that there are some solutions to knock the most silent,however, we do not know the solutions which is the most effective to cut down knock noise exactly.
To address this problem, we developed that the noise of ballpoint pen knock is involved in angle when we knock and in materials.

1 Introduction

3Result(1) Purpose

Experiment①↓

on class.
(2) Hypothesis①

The ballpoint pen knock noise is the quietest when we knock
ballpoint pen at an angle of 45 degree from plane.

②

The ballpoint pen knock noise is the quietest when we knock

the volume of ballpoint pen knock

We are distracted by ballpoint pen knock noise, so we do not focus

ballpoint pen on the fabric of the skirt.

2 Methods

20

・An ordinary noise machine was placed near the ballpoint pen for

16.827

15
10
5.127
5
0

*Common subject matters15.592

15.17590 degree

60 degree

45 degreea general way

Experiment②↓

measurement.
25

performed averaged.
・Check the volume when knocking in a general way.
（Figure 1）①

The volume at 90degree, 60degree, and 45degree were
measured. (Figure 2)②

The volume were measured on four types of materials: anotebook, a skirt placed on a desk, a skirt worn, and an eraser.

the volume of ballpoint pen knock

・In all experiences, 50 trials per parson and 100 trials by 2 people

21.98518.201

20
15

8.401

10

6.408

5.127

5
0
notebook

skirt×desk

skart

worn

erasera general way(Figure 3)

4 Discussion
Since experiments ① were conducted on the desk, it is probablethat the noise echoed on the desk and values increased overall. In
particular, it is probable that the values increased because a larger（Figure 1）(Figure 2)

force was applied to knock at 60degree and 45degree withoutslipping.
In experiment ②, the notebook and the skirt placed on the desk,
it is considered that they are thickness materials, so it echoed on
the desk, and the values became large. The noise on the skirt worn
was the lowest of the four materials, which is thought to be due to(Figure 3)

being absorbed by the feet. (The experiment of an eraser too.)
In conclusion, the quietest way was a general way.

How to hold the chalk without breaking it
2-5 15

1, Abstract

Isoda Kanon Araki Sayuki

Most of the teachers break chalks during class. When a chalk is broken, students lose concentration andthey should not waste resource. What kind of holding does not break the chalk? We find good way ofholding it using forefinger firmly.

2, Introduction

4. Result(1)Background(unit is gram)

①

②

③

④

⑤

⑥

Average

When we took a class, we noticed that some

A

-0.46

-0.36

-0.31

-0.42

-0.61

-0.6

-0.46

teachers often broke chalks, but some did not.

B

-0.34

-0.31

-0.35

-0.62

-0.5

-0.68

-0.467

We were interested in the difference between both

C

-0.4

-0.41

-0.38

-0.65

-0.64

-0.67

-0.525sides.

Figure2. The difference of group1’s weight(2)Hypothesis

Overall average is 0.484g.

The way to support a chalk at three points is best

①

②

③

④

⑤

⑥

Averageway. It is because the power affects a chalk equally.

D

-0.23

-0.32

-0.28

-0.52

-0.4

-0.14

-0.315(Figure1)

E

-0.24

-0.22

-0.21

-0.43

-0.38

-0.36

-0.307

F

-0.16

-0.17

-0.2

-0.44

-0.33

-0.3-

-0.267(Figure1)

3, Methods☆ We checked how much power broke the chalkin pilot study but we cannot inspect. So we focus
on only how to hold the chalk without thinking
the power.
(1)Ask teachers how to hold the chalk and stick

Figure3.The difference of group2’s weight
Overall average is 0.296g.Group1’s chalks
were more sharpened than group2’s ones andoften chipped.
〈group1〉〈group2〉
A

D

stickers on their fingers.
(2) Wrap a tracing paper around the chalk andcopy the position of the sticker into another chalkand make 6 of the same chalks by this way.

BE(3) Write“ん”from“あ”and “Z”from“A”about
1 and a half minutes in the chalk.(※1)(4)Weigh the chalk before and after writing tocheck how many the chalk dwindle. (※2)C

(5)Apply the vermilion ink pad to the chalk after
writing to check how many the chalk remain.
※1

Make top and bottom 30cm margins to writeat the level of ours eyesight.
※2

To break the chalk means that the chalk’s

top is applied. That is that chalk is worn out.

5. Conclusion

Group1 was more chipped than group2
because the part dyed red was small and top
was sharp.

Group1 is easy to break because force is applied with 1point on the blackboard and 2points on
the finger. In group2, the forefinger sticks to the chalk as a whole, so it is supported and hardto break.

F2-5 group: 16 Tokunaga Tamaki Iijima Kanon
Abstract
In classes, some teachers often break chalks. And we could not concentrate on our class because of it. However, wedon’t know the solutions. So we offer experiment from two points, the angle and the length. Then we learned thatchalks can be protected when held closer to the blackboard and in a less tilted position.

1. Introduction【1】Object
If chalks will not be broken, we can concentrate on our classes, and we can protect the earth.

【2】Hypothesis②length①Anglelsinθ

If the angle between a chalk and a blackboard
Ｎshorter, we can protect chalks better.

is bigger, we can protect chalks better.

Fcosθ

Ａcording to moment of force, M=Flsin²θ

According to the balance of the power, N＝Fcosθ

Fsinθ

So if the angle is bigger, chalks won’t be pushed.

F

2.Methods/Research

If the length between a chalk and a hand is

So if length is shorter, moment of force is smaller.

[1] requirement[1] requirement
New yellow chalks

Push the chalk[2] angle
and record theθ=15°30°45°60°75°90°

resultwhether※we also checked 50°55° as

be broken or not.

Pull the spring scale

New yellow chalks

and record the[2] length

weight when al=3.2 2.7 2.2 1.7 1.2 0.7

chalk turns.

[3] time

3timesan additional experiment[3]time3times15° 30° 45° 50° 55° 60° 75° 90°
○

○

○

○

×

×

×

×

The Force(N)60

3.Result40

r=0.91*

20
0

(20)

0

1

2

3

4

The Length Of The Chalk(㎝)From 15°to 50°→chalks was broken

The Connection Between The Length And The Force

From 55°to 90°→chalks was protected

4.Discussion

The longer the length is long, the bigger the momentof force is.

➀Chalks can be protected when held in a less tilted position.
②Chalks can be protected when held closer to the blackboard.

The Relation Between Surface Area Divided by Volume of Ice
and the Time for the Ice to Melt
2-6

Sayane Nakajima Waka Maruyama Marika Mizuno

1 Abstract
Whether it is applied to the ice that the larger body of animal is the less heat it emits was proved to be true inthis research by melting ice in an incubator.
2 Introduction

Figure 2: Time for ice to melt (second)
mass

①

②

③

④

⑤

⑥

average

25ml

288

298

224

244

237

198

248

bigger build than those living in the other areas. This

30ml

307

297

267

255

301

159

264

50ml

306

340

335

297

319

207

301

is because they can keep the heat in by making the

60ml

390

386

357

340

342

216

339

75ml

400

401

369

353

337

297

360

Animals living in the arctic and the Antarctic has

proportion of the surface area per the volume of their

Figure 3: Surface area, volume and surface area

bodies small. Then the thought occurred it might bedivided by volume

said the ice melts in the same rules. So, this subject

surfacemass

was set. In addition, the thought came up that thesurfacevolumearea(cm²)

(cm³)

area
dividedbyvolumetime which takes for the ice to melt is longer when the

25ml

52.2

27.3

1.91

surface area divided by volume of ice is small than it is

30ml

55.3

32.7

1.69

50ml

76.4

54.5

1.40

large as a hypothesis for this subject.

60ml

79.8

65.4

1.22

75ml

97.0

81.8

1.18

4 result
3 Methods

The next three graphs are showing the median of theFive pieces of ice were put in an incubator （fixed

result of the experiment which was carried out six

the temperature to 28℃）. They were made bytimes. (Graph 1, Graph 2, Graph 3)

pouring purified water in paper cups and each ice had
different volume, 25ml, 30ml, 50ml, 60ml, 75ml,
respectively. Each length of time from when they were
put in the machine to the moment when the first drop
separate from the ice was recorded. (figure 1)
These three graphs areshowing the median of figures
which measured in theexperiments.

Figure 1: Five pieces of ice in
an incubator

5 discussion
The graph of the time for the ice to melt in

The next two figures are showing the time which took

comparison with the surface area divided by volume

for the ice to melt in experiments and the information

seems to be a linear function. From this result, theof the ice : volume, surface area and surface area

hypothesis is said to be true. Also, it proved to be that

divided by volume.

the relation between the volume and the time to melt
is like a linear function. As a perspective, it might besaid that the change of temperature inside materials is
related to the surface area divided by volume.

How to study to get a high score on the word test
～memorizing words by writing them VS memorizing words by pronouncing them ～2－６ ７

Omi Kaori

Kikuchi Mayu

Abstract
When memorizing new words, which is the best way to memorize the word “memorizing it by writing” or“memorizing it by pronouncing?”
In this study, collaborators learned Spanish words in two ways “just read” and “just write”. It was investigated
However, no significant difference was seen.

１ Introduction

10

Results

point

3

correct(memorization by writing)

9

10
9
8
7
6
5
4
3
2
1
0

8

The purpose of this paper is to clarify which is7
65

better, writing many times or pronouncing many

4
3
2
1

1

the two methods for memorizing words, but thisstudy compare the scores of the words test whenmemorizing words by only one method.

4
5
Second collaborator

6

7
8
Third collaborator

910

speling errors(memorization by writing)

1

2

3

First collaborator

4

5

6

Second collaborator

7

8

Third collaborator

9

obvious errors(by writing)

10
8

2
1
0
2

3

First collaborator

4

5

6

point

Second collaborator

7

8

Third collaborator

9

3

4

5

6

Second collaborator

1

2

3

First collaborator

blank(by writing)

10

7

8

9

10

Third collaborator

4

5

6

Second collaborator

7

8

Third collaborator

910

number of times

blank(by pronouciation)

10
9
8
7
6
5
4
3
2
1
0

9
8
7
5

4
3
2
1
0
1

2

First collaborator

3

4

5

Second collaborator

6

7

8

9

10

number of times

Third collaborator

1

2

First collaborator

3

4

5

Second collaborator

6

7

8

9

10

number of times

Third collaborator

4 Discussion
These results lead to the conclusion that no matter

2 Method・３people cooperated in this experiment.
person to person , Spanish

9

number of times

obvious errors(by pronouciation)

10

6・Since English proficiency

8

number of times

number of times

10

The state of the brain when writing

2

point

1

The state of brain when reading aloud7

Third collaborator

10
9
8
7
6
5
4
3
2
1
0

9

3

hypothesis.

1

First collaborator

4

There is good evidence to prove the above

6

speling errors(by pronouciation)

10

5

times will give a higher score”

5

number of times

6“A test of words memorized by pronouncing many

4

Second collaborator

10
9
8
7
6
5
4
3
2
1
0

10
9
8
7
6
5
4
3
2
1
0

7

The following hypothesis was made.

3

First collaborator

number of times

point

Needless to say, it would be better to use both of

3

point

1
2
First collaborator

pointhigh score in a word test.

2

0

point

times, as a way to memorize English words to get acorrect(memorization by pronouciation)

point

which method was used to get a higher score in the word test.

greatly fromIt may not be that the collaborators mechanically did

used instead of

the work of writing the words and the work ofvarieswaswhich method was used to memorize the points.

English in this experiment.“pronouncing the words, and did the experiment with a・ collaborators memorized 10 Spanish words in 7

strong will to memorize the words.

minute ,then a spelling test was done on all 10 words .

Therefore, the effect of memorizing words by writing

・The words test was performed 20 times: of the 20

and the effect of memorizing words by pronouncing

test ,10 test ask the spelling of word memorized by

may not have been exhibited to the extent that they

writing ,and the other 10 tests ask the spelling of words

are reflected in the experimental results.

memorized by pronunciation.
・ The 20 test questions are all different, but thedifficulty of the test is the same for all 20 tests .

5 Bibliography
河島隆太(2003).『脳を育て、夢をかなえる』．くもんジュニアサイエンスA difference of memory between reading aloud and writing~By using Spanish words~
2-6 ➇ Akuzawa Moka
Abstract

Yasufuku Misaki

Testing two ways of remembering words in Spanish, only reading or only writing thewords, it might be able to get better scores on English tests by reflecting the result.
This research show that which is easy

resultto remember, to read aloud or to write within a certain

Graph.1

Purposeshows

averagetime. So, you could apply this investigation not only

scores under the conditions.

learning foreign language, but also your daily life.

From these graphs, there

Hypothesis Reading Spanish words aloud

was a slight difference between the two conditions, andcould be able to remember them well than writing them

there was not a difference statistically.

Graph.1

writing was 0.66 more than reading aloud.

However,

because one of the condition to memorize has
repetition. It is reading that we can repeat more during

Graph.2shows

the given time. Therefore, reading is better.

proportionofMethods

scored

No.1

per

the

pointsquestion.

From these graphs, therates were almost same inStudents were madeeithercondition.

to remember Figure1 in three

Reading was 4% more

minutes by reading them orthan writing in the casewriting them.

scored 1 point, whilewriting was 5% more

No.2

Figure1
They wait for athan reading in it scored2 points.

Graph.2

In addition, the case where the total score was 20

minute without doing anything.

points was 13% under the condition of writing and it

No.3

was10% under the condition of reading.
The Figure2 test wasdone by them.

Figure2

From these subjects, there being very few gap between＊How to score
・The spelling is correct

reading aloud and writing, it did not find which is better

２points

・One-letter deletion, insertion, and replacement
・ Other mistakes

Discussion
to remember the words. So we want to carry out additional
research on silent reading. If it is able to remember as

1points

many as reading aloud and writing, it will be useful in our

0points

life to remember something.

What kind of lights that discolor the most?
2-6 10 班

Karin Miwa Honoka Suzuki Aoi Sirakura＜background of making a decision＞

An incandescent lamp : The paper did not change

To prevent discoloration of important books and photos ofcolor so. But two weeks later,it changed color.

precious person.

Black light : Since a week had passed, its color quite had

The experiment that researching degree of discoloration ofbeen changing.

paper due to difference in light color couldn’t be run, since itLEDneeded a long period of time and a large room.

sample1 2.5Y 8/1 10YR 8/1 sample1 2.5Y 8/1 10YR 8/1

1week

2week

colorless 1week

2week

sample2 2.5Y 8/1 10YR 8/1 sample2 2.5Y 8/1 10YR 8/1<Hypothesis and Prediction >sample3 2.5Y 8/1 10YR 8/1 sample3 2.5Y 8/1 10YR 8/1

Black light is the most discolored paper,

ILB

Reason : The substance called `lignin`, the paper contain reacts

sample1 2.5Y 8/1 10YR 8/1 sample1 10YR 8/2 10YR 8/2

ultraviolet rays.

sample2 N 9,5

10YR 8/1 sample2 10YR 8/2 2.5Y 8/2

sample3 N 9,5

5Y 8/1

1week

2week

BL

1week

2week

sample3 7.5Y 8/1 2.5Y 8/2<Program of inspection ><Consideration>

Material: ・black light ・LED ・incandescent light bulb

Black light is the most discolored. It has great influence・cheap and low-quality paper x4

on discoloration to be exposed to ultraviolet rays, being

・cardboard ・shading seatsure.
Unexposed paper changes color ,too. It is found that

Why we use cheap and low-quality paper?
It is because cheap and low- quality paper contain lignin.

there are factors except for light ,so doing compound
experiments might be interesting.

Method : 1 , The devices was made.<image1>
Why the devices are covered with shading seat?

<image1>

Shading seat prevents other experiment from
affecting to leak light.
2 Four kinds of light in the dark room were gone with.
・black light・LED ・incandescent light bulb

・No

<image2,3>

Why we made no light?
It is because we want to go control experiment.

3 The degree of discolored paper was
examined with color leader every week.

＜An inspection result＞
Unexposed paper had changed color,too.
LED : It had the same result as unexposed paper.

<image3><image2>Investigation on using erasers～The situation of erasers when they have covers or not and are changed the angle～
２―６ １１ Rena Motosuga

・Breaking the eraser can be stressful

Karen Hayashi

・Weight of eraser dust(ｇ)
３０°

４５°

６０°

１

2.17

1.42

0.64

２

2.64

2.50

0.53

３

2.71

2.13

0.62

2.51

2.01

0.93

・With or without cover

average・The broken eraser is small andErase until the eraser breaks.

※Originally weight 11,3g

difficult to use

Find a way to make the eraser harder tobreak.

Change conditions
・Angle to erase the eraser

９０°・９０°did not function as a eraser

１Experimental equipment creation

・Only those with a cover broke

・The larger the angle of the erasers ,the easier break・The main cause of the eraser breaking

２Experiment

The eraser was broken the place
which is between it and the edge ofAngle : 30° 45° 60° 90°
Cover : with without

its cover.
The eraser is cracked due to eating
into the cover.

8 patterns in total
3 times eachBreak

2-6 ⑬ Mayuna Tsukada , Yui Bannai , Mahito Mori

Abstract
What is the trick of efficient wind power generation? For the purpose of figuring it out, the research of the angle ofthe blades to the wind was carried out.

1 Introduction

3 Result

Purpose: Making it widespread to generate power withwind, and contributing to provide environmentally

Figure 1
15.0

The average length of string
11.2

sustainable energies.
Hypothesis: Since current Dutch windmills are used

n=16

10.0

at 45°, at that degree to the wind,㎝

the windmill would spins most.

5.0

6.8
4.3
0.0

2 Methods & Research

0.0

0.0
0°

30°

45°

60°

90°

Figure 1 shows that at 30°to the wind, the windmill
spun most. At 0°and 90°, it did not spin at all.

Figure 2
Device A

Windmill

15.0

Picture2

Picture1

10.0☆These devices were used.
※Picture 1 shows the “Device A” used in order to makewind uniform.

9.1

9.7

n=15

7.5

6.5

㎝
5.0

0.0

※Picture 2 shows the windmill.

20°※Picture 3 shows form of all devices.
Device A

The average length of string

25°

35°

40°

Figure 2 indicates that the windmill spun most at 25°.
Windmill

4 Discussion
In order to maximize the number of times spin, two
factors are predicted. At 30°, wind power is stronger
than any other angles. In addition, it probably gives thestrongest “lifting power” and the least “drag” to thewindmill.

Picture3

Fan✴
The length of the twining around windmill was measured.
✴
Each experiments were done for 10 seconds.
✴
The distance between windmill and Device A was 15 cm.
✴
Wind was generated by fan, and wind speed was 0.8[m/s].

5 Reference

A windmill spinning with lifting power

http://www.kobe-kosen.ac.jp/~waseda/wtgpapermodel/2017-wtgpm-introduction-J-wl.pdf『磁石ナビ | 風力発電の基礎シリーズ（6）』https://www.neomag.jp/mailmagazines/topics/letter201205.html『揚力型水平軸風車（風力タービン）が回転する仕組み超入門（β版）』Development of a cloth mask free from uncomfortableness~What kind of cloth does prevent the air inside the mask from getting too hot?~Group122726 Asumi Terada / 2719 Nanami Kogure【Abstract】
While cloth masks are needed by more and more people, it is concerned that people wearing masks are likely to beheatstroke in summer. To solve this problem, we tried to find out what kind of cloth prevent the temperatureinside the mask from getting too hot and humid, using 8 kinds of clothes. It is quite difficult to major how thecloths can block the virus, so we mainly focus on only temperature and humidity inside the masks.

【1】INTRODUCTION～ Back ground of Research～
It is very uncomfortable to live wearing a mask in hot
summer days.
To identify which kind of cloth can keep the air
condition inside masks less hot and less humid, we

t1:temperature in first experiment t2: temperature in second experimentconducted a research.

h1:humidity in first experiment h2: humidity in second experiment

2)【2】METHOD AND RESEARCH

Ginguham

1 ） Research for Relationship between

Corduroy

Seersucker

Satin

Denim

Broad

Change ofTemperature inside beakers and Kind of Cloths.
▽8kinds of cloths…tweed, corduroy, satin, broad,

sheeting

denim, gingham, sheeting, and seersucker
thermometer

Thermo&hydrometer

25℃～
beekerTweedhomeothemic bathtab

40℃【4】Discussion
It is unclear that which kind of cloth can keep the air
inside beaker less humid and hot.
We could not associate research 1 and 2.
→Using too many kind of cloths, we could not conduct＊the temperature and humidity displayed on hydro&thermo-meter vary

research only two times with each cloth,

every four minutes. However, its span could not control strictly.

There were differences of temperature and humidity２） Observation of Surface of 8 Kinds of Cloths witheven when same kind of cloth was used.

binocular stereomicroscope.

→We could not control the temperature of the room【3】Result1) Only one of the graphs are placed. (See anothersheet for other graphs.)

where experiments are conducted.
【６】Reference
Yomiuri newspaper online https://www.yomiuri.co.jp

Best position of masking tape
2-1 Tanaka Yui

1 Abstract
This study is about masking tape. Four ways of pasting were tried and decided the most difficult way tocome off.
This conclusion, the way of putting on two places up and down was the best.
From this result, it is better for masking tape to paste in the middle than in the corner.

2 Introduction

3 Methods/Research

Masking tapes are easy to move, but attractive

・Tools eight pieces of paper, masking tape, wall

tools.

・Eight pieces of paper were put it with masking

But it is going to be peeled soon, so there might betapes on the wall. Four pieces were peeled by thea craft that cannot be peeled.

window. The others were not by the window.

This search’s purpose is to examine how to paste

Length of a masking tape was 5cm, the wall-to-that cannot be peeled the best.

paper ratio of adhesion was one-to-one. 2-stage

Hypothesis is masking tapes put it on four corners,

configuration. By the window ⇒A Not ⇒Bsideways, and the wall-to-paper ratio of adhesion

・Period 10.26～11.24

of it is one-to-one.

・①Four corner leaning ②Four corner sideways③Four corner lengthwise ④Two places in the
middle up and down

4 Result

A

B

The number is in order of hard to peel off.

①

②

③

④

No,2

No,4

No,3

No,1

Gap in the tape was

Peeled off at lower

The tape was loosen

No change

expanded.

left.

and twist.

No,2

No,4

No,3

No,1

Gap in the tape was

Peeled off at right

The tape was loosen

No change

expanded.

side.

and twist gradually.

5 Discussion
・It may be better for masking tape to paste in the middle than in the corner.
・Pasting in the corner, gap is born in the middle of paper, and expanded, so it may be going to take it off.
・③ was seen a twist, wind generated from motion of people may have effect on it.

２－２

Ｎａｋａｇａｗａ Ｍｉｓａｋｉ

Ｎａｋａｍｕｒａ Ｈｉｎａ

In summer, even the skin with sunscreen will burn. The interval to reapply sunscreen becomes clear by knowing
sunscreen effect time. To address the problem, we examine the UV intensity of each elapsed time, with and without
sunscreen and it turns out the effect time of sunscreen can be predicted to be about 20 hours under normal time,and it turns out it is about 4 hours under sweating.
㎼

The skin is burnt even if it wears sunscreen in thesituation of doing club active outside in the summer.
The skin can be prevented from burning even a little byclarifying the effective time of sunscreen and knowing
when to reapply sunscreen.
<Hypothesis>
Normal time ; keep effect for 2hours
When sweating : keep effect for 0.5hours㎼

Prepare three cardboard boxes with cellophane on the
top.
A:Nothing is applied to cellophane
B:Sunscreen was applied to cellophane
C:Sunscreen was applied to cellophane and sprayedwith water.
Place A, B, C in a sunny place and measure the UVThis experiment was depended on the climate. The

intensity in each cardboard box with a UV intensity

experiment was conducted from autumn to winter andmeter.

the UV intensity was weaker than in summer, so it was

When the UV intensity of B and C approaches the UV

not possible to know for sure how long the sunscreen

intensity of A, the sunscreen is no longer effective.

was effective. From the results, the effective time ofsunscreen under normal conditions is about 1/5 of thatwhen sunscreen is not applied, and about 1/2 of that

Two experiments were conducted.

when sweating is not applied. It can be predicted that

① Measure every 5minutes → 2hours 10minutes

the effective time of sunscreen in 20hours under↳The final UV intensity of B is about 1/6 of A.

normal condition and 4hours under sweating. Next, we

The final UV intensity of C is about 1/2 of A.

want to experiment in the strong UV condition in②

Measure every 20minutes → 4hours↳The final UV intensity of B’ is about 1/5 of A’.
The final UV intensity of C’ is about 1/2 of A’summer.

Is it true that drinks can dissolve teeth?
2-2 group7 Kogure Ayaka Sato Maine Sato Yuna
Abstract
We heard that drinking Coca-cola can dissolve our teeth, so we conducted this experiment. We soaked the
backbone of the saury in various drinks to see if would dissolve. The result was that the one soaked in lemon
juice dissolved the most. This suggests that acid is responsible for the dissolution of bones.

1. Introduction【Graph ２】
5.5[1]Background of the theme decision
We have often heard that drinking Coca-Cola can

5.0

dissolve our teeth, so we want to find out, regardless of

4.5

whether it is harmful to our body or not.

4.0

[2]Hypothesis

3.5

We think the more acidic the liquid, the better the

4.9

5.0

5.0

5.0

3.16

4.55

5.09

6.96

4.7
3.8

3.0
2.89

3.03

bones dissolve because we have learned the following
chemical reaction formula.

３. Result
CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂① The bones soaked in lemon juice became theshortest. The visual change was also very

2. Methods

large. (Graph２)《１》Soak the bones and liquid in a cup for a month andmeasure the length every day.

② For water, carbonated water, and soy sauce,
there was almost no change in length or《２》Measure pH and the sugar content of the liquid.
〇 Calcium phosphate, the main component of teeth, isalso the main component of bones. So the backbone of
the saury, cut into 5cm pieces, was used in place ofthe teeth.

visual appearance. These three liquids werealso the three with the highest pH values
among the liquids. (Graph２)③ The highest sugar content of the liquid wasin the soy sauce but the lemon juice, which

Use of objects ※40ml were used for each drinks
・Backbone of the saury

・Aquarius

・Waterdissolved the most, did not have a very highsugar content. (Graph１・２)

・Lemon juice

・Coca-Cola

・Vinegar・Coca-Cola Zero・Soy sauce

・Fruit juice (100％Apple juice)

4. Discussion
There is a relationship between the length ofbone discussion and, pH, and it is found that・Carbonated water【Graph１】

High sugar ranking

fluids with low pH values, which indicate strong
acidity, dissolve bone.
Sugar content does not have much to do with1

Soy sauce

34.4

the dissolution of the bones because the length4

Lemon juice

7.8

and appearance of the bones do not change even

9

Water

0.0

when the sugar content is high, as in soy sauce.

IN ORDER NOT TO ISSUE A SOAP SCUM IN HARD WATER
2-3

Sasaki Haruka

Takami Maya

ABSTRACTAs a result of adding familiar chemicals to hard water and detergent in order to find a way to prevent soap scumeven when using hard water and it was found that the use of acidic substances improved the fluffiness and prevented
soap scum.

METHODS &RESEARCH
EXPERIMENT ①

EXPERIMENT ②

The reason there is a difference in foaming

To fill the difference in foaming

METHODSMETHODS①Put 100 ml of hard water and soft water in a beaker,①Put 100 ml of hard water in a beaker, put 0.1 ml of

add additive-free detergent and synthetic detergent,

additive-free detergent, and put 2.0 g of chemicals.

respectively and make a total of 4 types of aqueous②Mix in a beaker 50 times with a whisk

solutions.

③Observe if the detergent is foaming②After mixing with a glass rod, observe

RESULT
hard

Additive-freewater

It became cloudy white andsoap scum was formed.

Synthetic

It can't make soap scum

Soft

Additive-free

It can't make soap scum

water

Synthetic

It can't make soap scum andfoams well

Sodium chloride

to become cloudy

Potassium chloride

to become cloudy

sodiumto become very white and muddyhydrogencarbonate

the bubbles disappear quickly

citric acidcolorless transparency

keep foam long

Lactic acidcolorless transparency

foam long

Carbonated watercolorless transparencyrough foam but

long lasting

CONCLUSION
Soap residue does not come out when using acidic substances and turned out to foam firmly.
This is because hard water and detergent are alkaline neutralized by acidic substances, soap scum turned into watersoluble or it is thought that it is because soap scum can no longer be formed, or it is thought that it is because soap
scum can no longer be formed. In the future, I would like to find out whether the soap scum has changed to one
that dissolves in water or whether the soap scum can no longer be formed.

REFERENCE
https://www.evian.co.jp/
https://contrex.jp/sp/about/component/index.html

andA search for a relation between water hardness and hand soap bubbles
2-3 Group5 Ozu Momoko Ogiwara Kaho

Abstract
We researched the relation between water hardness and babbles with handmade water softener. It was found outthat water hardness affects water’s lather.

１Introduction(1)purpose

10times filtered water’s hardness is 0 ㎎/ℓ.

It is known that water foams well compared to hardwater. To know what it has to do with hardness and3 Result

bubbles in detail, we started this research.

(2)Hypothesis
The lower the hardness of water, the higher the foamlayer.
※Bubbles layer is defined as good foam.

2 Methods①To reduce the hardness of water, a plastic bottle, ion
exchange resin and a filtration matt are used.(figure1)② Water classified into
the number of times
they were filtered.
③ Whipup

・It cannot be seen the difference between 20 ㎎/ℓ and
15 ㎎/ℓ．
・０㎎/ℓ can be seen a clear advantage.

each・Scarcely any bubbles are seen in the 100 ㎎/ℓ.

water10times with handsoap.

4 Discussion(figure1)Handmade water softener④Measure the height of the

The filtered water became more foam than water, but

bubbles

there is hardly any difference between 15 ㎎/ℓ and 20

and

seek

the

average of the level of the㎎/ℓ.

bubbles each time.(figure2)

Therefore, low hardness water bubbles well comparewith water. However, foam is not in direct proportion(figure2)A layer of bubble

to water hardness.

And then, we researched water hardness with ION
SELECTIVE PACKTEST.（figure3）
Nonfilteredwater’s

5 Referance

hardness is 100 ㎎ /ℓ.

「Serbian Walker のブログ」

3timeshttps://www.serbianwalker.com/blog/

filteredwater’shardness is 20 ㎎/ℓ. 5times「モリモリ！美容ブログ～お肌と財布と、地球に優しく♪」filtered water’s hardness ishttps://link.blogmura.com/out/?ch=10079358&url=http%3A(figure3)A PACKTEST kit 15 ㎎/ℓ.

%2F%2Fnonnonspring.blog98.fc2.com%2F

Natural Material for Sponges
2-5 group 5 Yakumo Ishii, Lisa Kaneko
1. Summary
Sponges we use in our lives are made of plastic. They are bad for the environment because most of them are
made of oil and disposable. Plastic wastes are said to cause marine pollution. To address the problem, we
examined what is the most useful natural material for washing oil stain out.
2. Introduction

4. Discussion

Target of our experiment①cottons and palms connected with more oil.

…Loofah/hemp/cotton/palm/absorbent cotton→a thread of cottons is made by twisting its fibers.

① Connecting the targets with oil→a fiber of palm is rough.

Weighing the mass of the targets before theexperiment and after that.

②absorbent cottons could absorb and maintained.
→ absorbent cottons’ fibers is the thinnest andconnecting most complex in the targets.
①②the more target absorbed water ,the least target
connected with oil.

② Making the targets absorb water(Absorbed water)→absorbed water kept oil from connecting with.

Make the targets absorb water as possible as
they can. Then weigh the mass of the targets
before the experiments and after that.
③Observing the targets
Observe the fiber of the targets by a microscope.

Palm(×4.0×10)

Cotton(×2.0×10)

Observing the fivers of the targets by a
3. Result① stereomicroscope
1[g]
2[g]

3[g]

Average[g]loofah

0.29

0.23

0.02

0.18

hemp

0.12

0.18

0.21

0.17

cotton

0.16

0.64

0.32

0.37

palm

0.41

0.10

0.34

0.28

absorbent

0.10

0.47

0.18

0.25

Absorbent cotton(×2.0×10)
5. Conclusion

In those experiments, the best target was different

cottoneach experiments. So the best material for both points

sponge

0.20

0.13

0.20

0.17

②

1[g]

2[g]

3[g]

4[g]

Average[g]loofah

5.55

6.47

4.85

6.73

5.90

hemp

6.39

6.10

10.29

9.61

8.10

cotton

16.27

3.11

4.90

6.15

4.72

palm

6.20

4.15

5.62

6.33

5.58

absorbent

23.63

21.28

18.86

20.49

21.07

18.3

19.29

20.73

23.73

20.51

cottonspongeLoofah(×2.0×10)

was not found.
The targets used in this examine on the market. So
the surface area, mass, and volume could not be
unified. This seems to be a cause that led the results
unexpected.
While those would be unified, we would like toexamine about the natural materials’ skill to wash oilthat be leaved for longer time and set.

2 年 7 組４班 王佳妮 梶間 瑠湖

[abstract]
In order to use erasers without as much waste, we thought about how to recycle the used erasers.
At first, we tried to melt and reshape them, but since we needed a large-scale equipment, we changed our experiment toforming an eraser using a binding agent. When Chikaballoon and glue were mixed at a ratio of 1:2, it was easiest to erase.

[introduction]

Verity if the eraser can be

Purpose: Use a small worn-out eraser without waste
Verification content: ①Melt and moldreconstituted by doing ①and②②Use a binder to combine an eraser〔Methods/Research〕
Experiment１：①Mix ethanol and essential①③

The experiment was not possibleoilbecause the equipment ajailable at

as a plasticizer and heat →Ignited

school is not large enough.

②Put an eraser in a pan and heat it →Burnt

２②③Hot water →Not a high enough temperature

３

Experiment２：Use Oyumaru as a binding agent→it becomes clay-like and as weak adhesive①

strength, making it unsuitable.
Experiment３：Harden the gum and eraser,②

Harden the chikaballoon and eraser. Grind themand mix with chalk.→They would not erase and０．
５chalk powder was not suitable.↓ｇ

Try using gum, chikaballoon and glue as a link
Experiment４：Mix the gum with an eraser andchange the combiration of ingredients and compare
the ease of erasing.→The one that was mixed

and chikaballoons.→0.5/1.0 is the best

１．０ｇ

０．２５ｇ

１▲２×３〇

１△２○３○

１▲２×３◎

①

Chika

１．
０
ｇ

completely was the easiest to erase with..
Experiment５：Find out the optimal ratio of glue

０．５ｇ

①
②

[Disscussion]

1.
0

Chikabaloon serve as softeners and bindingｇballoon②
Glue
１◎２◎３○

１×２▲３×０．３ｇ

０．４ｇ

３、Amount of eraser residue

Besｔ：◎ Good: 〇 Soso:△

The glue is softened by chikaballoon and can be easily①

reformed ,making it easier to contain the eraser.

②

Chikaballoon：Glue=<0.5：1.0 >or<1.0：2.0〉

２．０ｇ

When it is dried, it loses moisture and become hardens, so it

１、 The ease of erasing
２、 deformation

１×２×３▲

agents.

１△２◎３○

１○２×３×

Bad: ▲

worse：×

１．０ｇ

０．５ｇ

０．７５ｇ

１◎２△３○

１×２▲３×１○２△３▲

becomes difficult to deform and it becomes more difficult to
deform and it becomes easier apply force.
This way is enough to recycled the eraser, but it cost time andlabor,so we try to recycled more easily.

[Referance] ・「 消 し ゴ ム 工 場 ｜ ト ン ボ KIDS ｜ ト ン ボ 鉛 筆 」
https://www.tombow.com/sp/kids/eraser/factory.html

・・「消しゴムはどうやって作られる？自由研究にも使える家庭でのつくり方も」 ttps://cocoiro.me/article/27911

Effect of sunscreen ～Focusing on PA content～
2nd grade M.Oshima M.Kawahara＜Abstract＞

We focused on UVA, which is said to have the greatest effect on humanskin. Then, the bananas were coated with sunscreens with different PA
contents and exposed to sunlight. As a result, no change was seen in
the banana peel.
＜Introduction＞⒈ Purpose
To know the difference between
the effects of PA2⁺and4⁺⒉ Provisional
Reapplying PA2⁺ every two hours
has the same effect as PA4⁺.
＜Methods/Research＞⒈The banana peel was put atransparent cellophane tape on(The banana had been placed in
the darkroom for two days before
the experiment day).
⒉ On top of that, we apply 0.3g
of each sunscreen. And we put it

BeforeAfter＜Discussion＞
One of the reasons for the
failure was the lack of sunlight.

in the sun for 5 hours.
⒊ We wrap the banana in aluminum

So there was no change in thebanana peel. The other is thatfoil and leave it in the darkroom
for two days.

sunscreen manufacturers aredifferent. Therefore, theexpected result was not obtained.

＜Result＞
The experiment was repeated 4times, but the color of thebanana peel did not change.

＜Reference＞
http://anessa.shiseido.co.jp/shigaisen/spf_pa/

A weed-killer that can be made at home without chemicals
2-7 Team⑧ Kaori Kitadume Yukino Takada Yuki Nagao
Abstract
This research was done for the purpose of making the mosteffective weed-killer which was harmless for both humanbody and environment. This experiment was conducted bychanging concentration of acid or alkaline things. As a resale,
10% solution of citric acid whose pH was the smallest
worked the best.

１，Introduction

item(ⅰ)item(ⅱ)

item (ⅲ)

item(ⅳ)（１）Purpose
To make a weed-killer that is harmless for yourselves
and environment.

（２）Hypothesis
Weed can be killed by acid things or alkaline things.
Examplevinegar, citric acid, bicarbonate.

（３）The conclusion of tentative experiment
It is considered that acid things can kill weeds.

4，Discussion

2，Methods

General cells cannot grow outside pH from 4 to 8.

①make pots by using plastic bottles※ pH from 4 to 8 ＝ Ⓐ②plant weeds that are the same kind and size in them<tentative experiment>pH③spray water on them 10 times with a sprayer

Difference
from Ⓐ④make the following liquids（ⅰ）A 10% solution of citric acid5% vinegar

About2.7-1.3（ⅱ）A 5% solution of citric acid

5% citric acid

About1.6-2.4

5% bicarbonate

About8.5+0.5& A 5% solution of vinegar（ⅲ）A 5% solution of citric acid
&A 5% solution of bicarbonate（ⅳ）Only water

5% acid worked because there is the largest
difference from Ⓐ.
<This experiment>

Spray each liquid on weeds 20 times

pH⑤Observe the changes of color of weeds

Difference
from Ⓐ

３，Result

(ⅰ)

1.4

-2.6

The pictures on the upper right are the looks of weeds

（ⅱ）

1.9

-2.1

that are left for 1 week after the operation ④.

（ⅰ） worked better because there is larger difference

The root of item(ⅰ) and item(ⅱ) became red.

from Ⓐ than (ⅱ).

Especially item(ⅰ) changed markedly.

5，Reference

Item(ⅲ) and (ⅳ) had hardly changed for 1 week.

https://kagakucook/citric-aid-ph

It is because acid (citric acid) and alkaline(bicarbonate)https://www.mashley1203.com/entry/2019/07/14

were neutralized.

/063000

2-7-9 kaho ikeda

haruna nakajima

Be interested in sunscreen performance. So we researched sunscreen resistance by changing
condition, and considered.

Why we set this theme is that makes it easierFirst, the sunscreen is put on our palm a circle

how often sunscreen should be put on by

five millimeter in diameter and spread theknowing how much water will remove it. And

side of a 3 cm.

we think it is useful for our l daily life.

Then the water that changes the temperatureof 40℃ 30℃ 20℃ 10℃ is dropped from 15cm
30cm 45cm each.
Finally,

comparehowmuchsunscreen

remove after water.

10℃

20℃

30℃

40℃

15cm
30cm
45cm
※Left side pictures show before and right side pictures show after.

・The higher water, the more pressure, the easier the sunscreen was dropped.
・The temperature and pressure that cannot drop sunscreen is 15cm-10℃ 15cm-20℃ 30cm10℃.

2-7 Satsuki Kitazume

Moe Yamada

Result＆Discussion

Abstract
When we go into the water, there’s fear that sunscreen

Experiment1

might come off and get sunburned.

So, the purpose of our study is to enhance the abilityof water-resistant in the water without spoiling theeffect of protection from the sunlight.

Normal→come off best
Jojoba oil→not come off easily
Castor oil→not come off easily
Conclusion: Sunscreen with oil is stronger to water.

Hypothesis

graph

Sunscreen mixed oil can remain on theskin longer than normal.

Way of study＊research of water resistance○
1 Spread sunscreen on black stocking as a substitute forskin. (picture 1)
2 Steep black stocking in water, survey the color○(brightness and chroma) of sunscreen every 1minutes.
3 Read the data showed by a color reader.
○＊research of resistance to ultraviolet rays(UV rays)

It turns out mixing oil can repel water.
Therefore, emulsification can stronger water resist.
Experiment 2○
1 Spread three types of sunscreens (A original B mixed
Castor oil C mixed Jojoba oil) on a plastic folder

E＆F→a clear plastic folder does not influence to result.
D＆E→spreading something does not influence to result.

respectively○
2 Expose them to the sunlight, using apparatus

B＆C→mixing oil does not spoil effect of protection fromthe sunlight.

illustrated picture 2.
○
3 Compare figures among them (A～F).

A＆D→a sunscreen protect from UV rays.

table
A normalUV

B mixed castoroil
0

D creampicture 20

E clear plastic folder F none46

picture 1

C mixed jojobaoil
06485