Download A.6 Review questions key

Unit Test 2
“Some “ Review Questions
1. Name the force of ATTRACTION between electrons and protons :
___________electromagnetism_____________________
1. Gravity: Mass is attracted to Mass
2. Strong Force: the force between the protons and neutrons of the nucleus of
atoms. It holds the nucleus together.
3. Weak Force: An attraction between hydrogen atoms. Causes nuclear fusion
between hydrogen atoms, it is the reason the sun burns. It also causes
radioactive decay.
4. Electromagnetism: Attraction between charged particles (e.g.protons &
electrons). It is the force that holds atoms together.
2. State the law of conservation of energy:
_____________energy neither created nor destroyed just
transforms________________________________________________________
________________________________________________________________
___________________________________________________________
3. List the first three elements formed in the beginning of the universe. Circle the
simplest one:_________H He
Li____________________________________________
4.List the energy transfers and transformations below:
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Transfers : __________wind ( KE) to propellar ( KE )
________________________________________________________________
______________________________________________________
Transformations : ___________wind to electricity ____potential to
kinetic___________________________________________________________
______________________________________________________
5. Explain how galaxies form:
• Clumps of dark matter attract Hydrogen and Helium gas through the force
of gravity
These clouds form huge clouds will eventually become galaxies
6. Explain how stars form :
•
•
•
A star is formed when a large amount of hydrogen gas starts to collapse on
itself due to gravity.
As the atoms collide they release a lot of heat energy.
Eventually colliding nuclei hydrogen will fuse and form helium. This
nuclear fusion causes a huge release of energy like a nuclear bomb. This
nuclear fusion is what causes stars to burn
.
7. Draw and label a lithium atom:
Li : 3 e, 3 P, 4 N
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8. Draw and explain the Doppler effect:
Drawing:
Red

Blue
9. State the Big Bang theory:
According to the Big Bang model, the Universe expanded from an extremely dense and
hot state and continues to expand today
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10. Put in the correct chronological order ( i.e which came first to last):
big bang, first atom, solar system, life of earth, dinosaurs, humans
11. Explain how you can tell if something is going away from you in terms of the
pitch of the sound and the color it changes:
Red

Blue
12. Since stars and galaxies are moving towards/away from each other this
proves that the universe is shrinking/expanding. One effect that helps to
explain this theory is called the violet/red shift and is further evidence for the
____big____ _____bang____ theory.
13. Explain the statement that humans came from stars:
Big bang stared universe and stars responsible for first atoms and all other
elements . Elements make life = humans
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14. Which has more energy red light or blue light? Why?
Blue = higher frequency = higher energy
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