# Practice Problems

Students - please put in two questions for the review and work out entire example.
Make sure to include all equations and units. Make sure to tag your question with --~~~~
If possible make these questions multiple choice.
Thank you.

## Graph Reading

According to the graph above, how many dollars were saved in the 5th year of energy conservation? a. 100 b. 300 c. 450
* According to the graph above, during what year did the biggest drop in money saved occur?
a. years 3-5 b. years 2-4 c. years 7-8

## Nuclear Energy

* How much energy, in MeV, does a fission of a uranium atom let off?
A. 150 MeV B. 10,000 MeV C. 500 MeV D. 200 MeV
* The following diagram is an example of what?
A. Nuclear Bomb B.Electrons C.Fission Reaction D.photons
* What is the difference between fusion and fission?
* If you have 34 protons and 23 neutrons, what is the nuclear number?
* A chain reaction of fission results in what?
* True or False: by slowing fission down you can possibly stop it?

### Types of radiation

* Out of the types of radiation that we talked about in class put the three types in order of least engery to most energy.
Answer: Alpha, Beta, Gamma
* What type of radiation can go through brick walls and can partly pass through lead?
A. Alpha B. Beta C. Gamma
* What does E$_B$ stand for in the equation: E$_B$=Δmc$^2$?
A. Blinding Energy B. Broken Energy C. Binding Electrons D. Binding Energy
* Why doesn't a nuclear reaction inside a nuclear energy plant get out of control when using Uranium 235?
A. Fuel Rods B. Water C. Control Rods D. Turbine
* Fill in the blank:
Kelly is standing 10 feet in front of a brick wall and is exposed to the 3 types of radiation alpha, beta and gamma. ________ goes through Kelly's body and into the brick wall, _______ only goes to Kelly's hand and stops, and _______ goes through Kelly's hand but doesn't go through the brick wall.
* What are the components of this equation A= Z+N?
a. A= atomic number, Z= electrons and N= neutrons
b. A= nuclean number, Z= protons and N= neutrons
c. A= atoms, Z= protons and N= nuclear
Answer: B
* Between the three types of different radiation, which of the three would go thru a brick wall?
* How can you protect yourself from the three types of radiation?
a. time b. distance c. shielding d. all the above
D is the correct answer
* One atomic unit equals_____?
a. 1.26 x10^-25 b. 1.66 x10^-27 c. 2.16 x10^-27 d. 1.46 x10^-7

### Natural Uranium

1. How much of natural uranium is used for energy?
2. What type of natural uranium is considered Fission? A. U$^{238}$ B. U$^{236}$ C. U$^{235}$

### DU

1. True or False: Natural Uranium is safer than Depleted Uranium.
2. Natural uranium is made up of two different types, what are they and which one is used for energy and which is a waste product?
3. What are the two main uses for U238?
4. True of False: Depleted Uranium is still being used today.
5. Why is Uranium 238 such a high profit substance for companies such as Aeroset/Honeywell?

## Electric Fields

* What is the equation for electric fields?
* What is the q equal to on the equation for electric fields?
a.force b.charge c. distance
* What is the distance between charges if the Electrical Field (E) is equal to 4 [N/c], the constant (k) is equal to 1, and the total charges in the system is 6?
a. 2m b. 1.22m c. 4m d. 10m

## Magnetic Fields

* What is Faraday's Law?
* What are the two ways to change the rate of change of the magnetic flux?
* The law that states, the magnitude of induced emf around a loop is equal to the rate of change of the magnetic flux through the loop, is known as what law?
A.Fourier's Law B.Faraday's Law C.Newton's Law D.Law of Thermodynamics
* Will the north pole of a magnet attract the south pole or the north pole of another magnet?
* What is the formula for a Magnetic Force?
* The magnetic force Fm on a charge q moving with a velocity v in a magnetic field B is given by Fm = q(v x B). Which of the following statements are always true?
a) Fm is always perpendicular to v. (b) v is always perpendicular to B. (c) Fm is always perpendicular to B.
* Which of the following is wrong?
a. + attracts - b. + repels + c. + repels - d. - repels -
* What does emf stand for?
A. Electromagnetic friction B. Electro magnitude force C. Electromagnetic force D. Electric magnetic friction
* _________________ states that the magnitude of the induced electromagnetic force (EMF) around the loop is equal to the rate of change of the magnetic flux through the loop.
a. Fuller's Law b. Huygen's Principle c. Faraday's Law d. Farrier's Law
* Does Faraday's law state that the magnitude of the electromagnetic force around the loop is not equal to the rate of change of the magnetic flux through the loop?
a. True
B. False
* If North and South ends are pointing towards one another what is the outcome?
* If you want to change the magnetic flux through the loop. which one is not the right way to do?

## Wave review

* What is the definition of a wave?
* What is the highest point of a wave?
A. trough B. crest C. amplitude
* When waves are tightly put together this means the waves have a _________?
A) High Velocity B) Low Frequency C) High Amplitude D) High Frequency
Answer: D) High Frequency

## Solar photovoltaic cells

* Out of crystal silicon, multicrystal silicon, and amorphous silicon, which has the highes efficiency as well as the highest cost?
* Which of the following solar cells work with a pn junction?
A.Crystal silicon and Amphorus silicon B.Multicrystallie silicon and Amphorus silicon C.Crystal silicon and Multicrystalline silicon D.All the above
* When a light photon is emitted through a pn junction it creates electricity. What happens when electricity is pushed through a pn junction? What is this also called?
* What does the n stand for in the pn junction
* Out of the three types of solar cells which is the cheapest to purchase?
A. Crystal Silicon B. Amorphus Silicon C. Multicrystalline silicon
* Out of the three types of silicon solar cells which is circular shaped?
* What are the economical benefits of solar research and energy efficiency research as it relates to the work force.
* True or False: Northwestern Pennsylvania is one of the best places in the United States for solar power use.
Of the following, which is not an advantage of Amorphus Silicon? A. high absorption B. it is cheaper than the glass, plastic, or metal you deposit on it C. it degrades when light hits it D. it is an established technology
* Of the three types of solar cells which one of them has a pin structure rather than a pn structure?
* What does it mean to live "off-grid"?