OpenLLM-France/wikimedia huggingface dataset:
# A-level Physics (Advancing Physics)/Capacitors/Worked Solutions

1. A 2 mF capacitor is connected to a 10V DC power supply. How much charge can be stored by the capacitor?
$Q=CV=2\times 10^{-3}\times 10=0.02{\mbox{ C}}$
Note that this is the maximum charge - since capacitors charge, as well as discharge, exponentially, we would have to leave the capacitor charging for an infinitely long period of time to charge it to capacity.
2. What is the highest possible energy stored by this capacitor?
$E={\frac {1}{2}}QV=0.5\times 0.02\times 10=0.1{\mbox{ J}}$
3. The capacitor is placed in series with a 5Ω resistor and charged to capacity. How long would it take for the charge in the capacitor to be reduced to 1 mC?
$Q=Q_{0}e^{-{\frac {t}{RC}}}$
$Q_{0}=Qe^{\frac {t}{RC}}$
$e^{\frac {t}{RC}}={\frac {Q_{0}}{Q}}$
${\frac {t}{RC}}=\ln {\frac {Q_{0}}{Q}}$
$t=RC\ln {\frac {Q_{0}}{Q}}=5\times 0.002\times \ln {\frac {0.02}{0.001}}=0.0300{\mbox{ s}}$
4. After this time has elapsed, how much energy is stored in the capacitor?
$E={\frac {1}{2}}QV={\frac {1}{2}}Q_{0}V_{0}e^{-{\frac {2t}{RC}}}=0.5\times 0.02\times 10\times e^{-{\frac {2\times 0.03}{5\times 0.002}}}=0.25\;m{\mbox{J}}$
5. What is the capacitance of the equivalent capacitor to the following network of capacitors?
First, ignore the fact that the capacitances are in mF, not F - we will not be using any other units, so if we put in mF, we will get out mF.
Then work out the equivalent capacitance of the second row:
${\frac {1}{\Sigma C_{2}}}={\frac {1}{1}}+{\frac {1}{2}}+{\frac {1}{3}}={\frac {11}{6}}$
$\Sigma C_{2}={\frac {6}{11}}{\mbox{ mF}}$
Then work out the equivalent capacitance of the third row:
${\frac {1}{\Sigma C_{3}}}={\frac {1}{2}}+{\frac {1}{2}}=1$
$\Sigma C_{3}=1{\mbox{ mF}}$
The equivalent capacitance of the first row is easy, since it contains just 1 capacitor: 3mF. So, the total equivalent capacitance is:
$\Sigma C=3+{\frac {6}{11}}+1={\frac {50}{11}}\approx 4.55{\mbox{ mF}}$
# A Beginner's Guide to D/Before We Begin.../Editors Supporting D

There is currently no finalized IDE tool ala Eclipse for D development. Vim and Emacs come bundled with D editing modes, and since D is syntactically very similar to the other C-style languages, any editor which supports those might rudimentally support D.
However, for an exhaustive list of D-supporting IDEs, please refer here.
# A Beginner's Guide to D/Conditions and Loops/Simple Branching

Programmers familiar with C, C++ or Java are likely to find this section familiar, and may want to skim or skip it at their discretion.

## The if Conditional

Example: More Complicated Input - a program that asks age and makes a "clever" response
# A Beginner's Guide to D/Before We Begin.../Short Introduction to D

D is a language following in the footsteps of the C-language family. It has the same general syntax, so anyone familiar with C, C++, Java or C# should be able to easily pick up the language. You should see the language comparison page for more details.
Since this page is about a short introduction to D, why not start with the all-famous Hello World.
For the experienced C programmer, the import and writefln should look strange. We will discuss them in later chapters.
# A Beginner's Guide to D/Conditions and Loops

Programmers familiar with C, C++ or Java are likely to find this section familiar, and may want to skim or skip it at their discretion.
This chapter introduces the basics of conditions and loops, the basic constructs of program flow.

## Table of Contents

* The Concepts of Conditionals and Loops
* Simple Branching
* Simple Iteration (The foreach loop)
* Simple Looping (The while and do-while loops)
* Complex Iteration: The for Loop
* Switch Statement (The Switch conditional)
# A Beginner's Guide to D/Conditions and Loops/Switch Statement

Programmers familiar with C, C++ or Java are likely to find this section familiar, and may want to skim or skip it at their discretion.

## Basics

The switch statement can be found in almost every programming language, it's commonly used for checking multiple conditions. Syntax is identical as it is in C++ or Java. It has following form:
Here's some simple example:
And the result of our code:
Note break keyword after each case! If it's bypassed each case after it will be called. So here's console output of code without breaks:
As you may see, all cases after /hello were "called", this is useful if we want to call same statements in more that one case. Here's one more example:
# A Beginner's Guide to D/Conditions and Loops/The Concepts of Conditionals and Loops

Programmers familiar with C, C++ or Java are likely to find this section familiar, and may want to skim or skip it at their discretion.
At this point, you should know how to do some simple interaction with the user. But without conditions or loops, your programs can only follow one simple pattern.
One fundamental capability of any programming language is conditions. A condition statement, such as an if statement, causes different code to run depending on whether a condition is true or false. if statements will be introduced in the following section.
Another important ability is a loop. It's often necessary to make one section of code run multiple times. The foreach, for and while loops allow this. They will be introduced later in this chapter.
# A Beginner's Guide to D/Conditions and Loops/Complex Iteration: The for Loop

The most complicated loop statement that D provides is the for loop. The for loop is borrowed directly from C, and shares its syntax. It has the following form:
The first set of statements are separated by commas, and are executed before the loop begins. Variables can be declared in these statements. This is usually used to initialize an index variable. The conditional is a Boolean value, and is executed before each iteration of the loop. The body is only executed as long as the conditional remains true. The last set of statements are executed after the body, and usually increments an index variable.
The following is the typical use of the for loop:
However, more complicated for loops are possible. For example, a for loop can iterate over two arrays, in opposite directions, at the same time:
# A Beginner's Guide to D/Conditions and Loops/Simple Iteration
## Simple Iteration: The foreach loop

The foreach statement provides a number of ways to iterate through an array in either direction. It takes as its arguments the name of a variable that will contain an element in the array, and the array to be traversed. It is followed by the statements to be executed. It is possible to obtain the index used to find a specific position in the array. In the following example we initialize an array of integers and iterate through it using foreach and foreach_reverse. You do not need to specify a type for the value.
As with the if statement in previous chapters, you do not need brackets if there is only one statement following foreach. It is worth noting the use of a comma instead of semi-colon between index and value.
The code prints out the following:
Cycling using foreach is done on a copy of the values, meaning that changes to them are not reflected in the originals. If we want to change the original array's values, that can be done by adding the type modifiers out or ref (equal to inout). The first can only be written to, the second can be read and written. If you attempt to read an out variable, it will be initialized. Adding the type modifier to an array index results in a compiler error.
Output:
# A Beginner's Guide to D/Conditions and Loops/Simple Looping

Programmers familiar with C, C++ or Java are likely to find this section familiar, and may want to skim or skip it at their discretion.
One of the simplest kinds of loops in D is the while loop. This loop will keep looping as long as its condition is true. This also makes the while loop very flexible—virtually any kind of loop can be written as a while loop, if you try hard enough.
A while loop looks like this:
The while loop will see if the condition is true, and if it is, it'll run the code inside it. It'll keep doing that until the condition is false.
As was shown in the last section, the foreach loop is useful for looping over the contents of some kind of container. But what about when you don't know how much data you have, such as when you're reading from a file? A while loop can help in this case.
So here we create an array of strings named names to hold a list of names we'll read in from a file. Then we create a File object. Remember in the Basic Input section, where we used din to read a line of text from the console? din is really a kind of File object, so we're doing the same thing here, except we're reading from a file on disk instead of from the user.
The important thing here is the while loop. Let's have a closer look at it:
The condition is input.eof == false. The .eof method of File means "end of file." So we're going to use this loop to read data while we're not at the end of the file. In other words, we're going to read all the data out of the file. The body of the loop does just that—it reads a line from the file, and appends it to the end of our list of names.
At the end of our program, we write out the list of names, using the familiar foreach loop.
A second, very similar kind of loop is the do-while loop. In a while loop, the condition comes at the beginning of the loop, but in a do-while loop, the condition comes at the end. The reason this is significant is that with a while loop, if the condition is false the very first time, the loop body will never be run, so while loops can run their bodies 0 or more times. But with a do-while loop, the body is run at least once before the condition is checked. do-while loops look like this:
One case where this kind of loop comes up a lot is when you're trying to get valid input from the user. Usually you ask the user to enter something in, then you check it to see if it's valid, and if it's not, you keep asking them until they give you something good. This is what a do-while loop is for: it'll run the input code at least once, and keep running it until the condition is met.
This code uses the valid variable to keep track of whether what the user entered was valid or not. It'll be set to true once they do. Until then, though, the do-while loop will keep looping, asking for user input.
# A-level Computing/AQA/Computer Components, The Stored Program Concept and the Internet/Consequences of Uses of Computing/Hacking

The term hacking can have two meanings:
* The term might mean that you have taken some existing code and hacked it to do what you want it to. For example you take pre-existing open-source game code and use it to make your own game with. This is legal.
* The other meaning is the more common, this is the idea that you break through some security system, bypass a copy protection, get access to data you shouldn't have access to etc. All this is illegal and sometimes termed cracking. Online financial and identity thefts are growing massively around the world.
| Richard Stallman is an example of an early day hacker, in the legal sense of the word | Gary McKinnon is an example of a cracker, having hacked into the US Military |
* Hacking Hats
* Within the hacking community, in the second sense of the term, there are two main groups.
* The term white hat in Internet slang refers to an ethical hacker, or a computer security expert who specializes in ensuring the security of an organization's information systems. White hats may flag up security vulnerabilities on corporate websites and bring them to the attention of companies or organisations before the bad guys can make use of them. Recently companies have recognised the use of white hats, with companies such as Facebook and Google offering bug bounty for people who can bring their attention to security flaws in their products
* A black hat is a hacker who "violates computer security for little reason beyond maliciousness or for personal gain" Black Hat Hackers are what the media will often talk about when talking about 'hackers'. Black Hats break into secure networks to destroy data or make the network unusable for those who are authorized to use the network. Examples include the Lulzsec hacking group that hacked corporate websites for the 'lulz', releasing thousands of user account details of companies such as Sony.

## References

* ↑ What is white hat? - a definition from Whatis.com
* ↑ R. Moore, Cybercrime: Investigating High Technology Computer Crime, 2005, Matthew Bender & Company, p258
# A-level Computing/AQA/Computer Components, The Stored Program Concept and the Internet/Fundamental Hardware Elements of Computers

* From the specification:
* Logic Gate:
* Construct truth tables for the following gates: NOT, AND, OR, XOR, NAND, NOR
* Be familiar with drawing logic diagrams involving one or more of the above gates.
* Boolean Algebra:
* Be familiar with the use of De Morgan’s laws and Boolean identities to manipulate and simplify simple Boolean expressions.
* Logic Gates
* Boolean gate combinations
* Building circuits
* Boolean algebra
** Simplifying boolean equations
** Boolean identities
** De Morgan's Laws
** Gate conversion
* EXTENSION:Uses of gates
# A-level Computing/AQA/Computer Components, The Stored Program Concept and the Internet/Fundamentals of Computer Systems/Application software
## General purpose application software

General purpose application software is a kind of application that can be used for a variety of tasks. It is not limited to one particular function. They provide a large number of features for its users. For example, a word processor could be classed as general purpose software as it would allow a user to write a novel, create a restaurant menu or even make a poster.
Examples of General purpose application software include: Word processors, Spreadsheet and Presentation software. Whatever you do, do not use brand names!

## Special purpose application software

Special purpose application software is a type of software created to execute one specific task. For example, a camera application on your phone will only allow you to take and share pictures. Another example would be a chess game, it would only allow you to play chess.
Other examples of special purpose application software are web browsers, calculators, media players, calendar programs etc. Again, make sure that you don't use brand names!

## Bespoke application software

Bespoke application software is tailor made for a specific user and purpose. For example a factory may require software to run a robot to make cars, however, it is the only factory making that car in the world, so the software required would have to be specially built for the task.
Other examples might include software for the military, missile/UAV operations, software for hospitals and medical equipment, software being written inside banks and other financial institutions.
There are several things to consider before purchasing bespoke software, on the plus side:
However, you must also consider
* Exercise: Application Software
* List and describe the three types of application software:
* Answer:
* General purpose software - software that can be used for multiple purposes
* Special purpose software - software built for a specific purpose
* Bespoke application software - software built for a specific user and purpose
* Give an example of each:
* Answer:
* (Don't let the examiner catch you using product names!)
* General purpose software - word processor / presentation software / spreadsheet
* Special purpose software - Web browser / media players / calender programs
* Bespoke application software - car robot control software / military control software
* Why might you choose to use general purpose software instead of bespoke software, why might it not be suitable?
* Answer:
* general purpose software is:
* cheaper than bespoke
* readily available, whilst bespoke may take some time to write
* able to perform multiple tasks
* probably less buggy
* However,
* it might not perform all the tasks needed by the user
# A-level Computing/AQA/Computer Components, The Stored Program Concept and the Internet/Fundamental Hardware Elements of Computers/Boolean algebra

We have met gate logic and combinations of gates. Another way of representing gate logic is through boolean algebra, a way of algebraically representing logic gates. You should have already covered the symbols, below is a quick reminder:
| Bitwise Operator | NOT(${\overline {A}}$) | AND(.) | OR(+) | XOR($\oplus$) | NAND(${\overline {A.B}}$) | NOR(${\overline {A+B}}$) |
| Description | invert input | where exactly two 1s | where one or more 1s | where exactly one 1 | where less than two 1s | where exactly two 0s |
For the exam you might have:
* to convert logic gates into boolean algebra,
* build logic gate combinations from boolean algebra,
* simplify boolean algebra.
# A-level Computing/AQA/Computer Components, The Stored Program Concept and the Internet/Fundamentals of Computer Systems

* From the Specification : Hardware and Software
* Understand the relationship between hardware and software and be
* able to define both.
Hardware and software
* From the Specification : Classification of Software
* Be aware of how software is classified.
* Be able to explain what is meant by system software and application software.
* Understand the need for and attributes of different types of software
Classification of Software
* From the Specification : System Software
* Understand the need for, and functions of, system software:
* Operating system software
* Utility programs
* Library programs
* Translator software (compiler, assembler, interpreter)
System software
* From the Specification : Application Software
* Describe the different types of application software and the criteria for selecting appropriate software for particular purposes.
* General purpose application software.
* Special purpose application software.
* Bespoke application software
Application software
* From the Specification : Generations of Programming Language
* Describe machine-code language and assembly language.
* Awareness of the development of programming languages and the
* limitations of both machine-code and assembly-language programming
* First generation - Machine code
* Second generation - Assembly language
* Third generation - Imperative high level language
* Explain the term imperative high level language and its relationship to first and second generation languages
* Fourth generation - Declarative language
* Explain the term declarative programming language and where and why declarative languages are used
Generations of programming language
* From the Specification : Types of Program Translator
* Define each type of language translator and describe situations
* where each would be appropriate.
* Assembler
* Compiler
* Interpreter
Types of program translator
# A-level Computing/AQA/Computer Components, The Stored Program Concept and the Internet/Hardware Devices

* Input and Output Devices
* Know the main characteristics, purpose and suitability of contemporary devices (see the Teacher Resource Bank), and understand their principles of operation, including methods of error checking (check digit).
* Secondary Storage Devices
* Explain the need for secondary storage within a computer system, know the main characteristics, purpose and suitability, and understand the principles of operation of contemporary devices (see the Teacher Resource Bank). Compare the capacity and speed of access of various media and make a judgement about their suitability for different applications
# Adventist Adventurer Awards and Answers/Troubadour

* Troubadour
* Builder

## Find, read, and explain the meaning of Psalm 66:1-2.

vteAdventist Adventurer Awards :
# Adventist Adventurer Awards and Answers/Weather

* Weather
* Little Lamb

## Listen to a book about weather.

https://www.youtube.com/watch?v=BgvbpxTX0rM

## Say three things you learned about weather.

* Rainbows have 7 colors - Red, Orange, Yellow, and Green, Blue, Indigo and Viliot
* Clouds send the rain
* You need sun and rain to make a rainbow
* God made the clouds, the sun, the rain and everything

## Play an action game about weather.

Thunderstorm Game Form the children into a circle. Together act out a thunderstorm.
* Wave your hands together back and forth for the wind.
* Put out your hands, wiggling the fingers as you sink to the floor for the rain.
* Stamp your feet or clap your hands to make thunder sounds.
Say wind, rain, thunder as the children perform each action. If desired, the children can take turns calling out the actions for the others to follow.
Rain and Rainbows Explain how rainbows are formed under just the right conditions of sunlight and rain. On a sunny day, go out and turn on the water hose, lifting it high so the water makes an arc. Light should reflect off the water to form a small rainbow, just as it does when rainn and sun are present together. Ask the students to identify all the colors in the water hose rainbow. Back inside, or at picnic tables outside the children can draw pictures of the rainbows and rain.
Cotton Ball Cloud Hand out a cotton ball to each child to act as a pretend cloud. The children should touch and squeeze the cotton ball and explain how it feels. Next, introduce a small tub of water and have each child to put their cotton ball in the water. Clarify to the children that this is what occurs when water evaporates and goes up into the cloud where it is chilly and therefore turns into water. Place all the cotton balls on a flat surface and ask each child to pick one up, feel it and discuss how it feels. Explain that the water is dripping from the "cloud" because it got too heavy with water and that makes rain.
Learn Rain Rain Go Away together and act it out.

## Make a weather craft.

Rainbows
Listen to and learn this catchy Rainbow Song and then color your own rainbows (with the colors in the right order).
Rainbow Art
Supplies:
* Coffee filters
* Markers
* Water
Use markers to draw colored arcs on half of a coffee filter, paint over the filter with the water, and watch the colors blend together.
WEATHER CRAFT 2
* paper plate
* crayons
* piece of paper shape like an arrow
First draw the four different weather options ,cloudy ,sunny, rainy and windy Secondly punch a hole in the middle of the plate and attach the arrow Lastly ha e your children go outside and choose the weather they see

## Extras

Weather Cards.pdf
vteAdventist Adventurer Awards :
# Adventist Adventurer Awards and Answers/Trikes & Bikes
## Listen to a book about trike & bike riding.

you can find the book Hello Bicycle in You tube"

## Sing a song about trike & bike riding.

Ride a Bike song in YouTube
Another Bike song

## Play a game about trike & bike riding.

* Obstacle Course --
Ask each child to bring his or her favorite set of wheels.To create the course, arrange orange cones or other soft items in your yard or a nearby park. Include curves, turns, and small hills. Fuel the kids' excitement by timing each racer as he or she pedals to the finish line.

## Make a trike & bike craft.

* Bike Parade --
Have your children decorate their wheeled toys and then have a parade.
https://someonesmum.co.uk/2018/06/14/easy-bicycle-craft-kids/
Lolly Stick Bicycle Craft – You will need
Cardboard hoops (craft shop wreath templates work well) or paper plates Lolly sticks. We used two sizes – the usual smaller ones and some large lolly sticks Paint Glue Any other decorations or embellishments you would like to use
# Adventist Adventurer Awards and Answers/Trees

* Trees
* Sunbeam

## External Resources

vteAdventist Adventurer Awards :