1. Energy Study Guide Review

2. What factors affect the GPE an object has and how?
Mass and height; the more mass and the higher from the earth’s surface, the more GPE

3. Green plants convert light energy from the sun into ___________energy.
Chemical potential

4. State the law of conservation of energy.
Energy cannot be created or destroyed. It can change form.

5. What unit is used to measure thermal energy? kinetic energy? GPE?
Joules is the unit for all forms of energy

6. Kinetic energy depends on what two factors?
Mass and velocity

7. Name some devices that use electrical energy.
A computer, toaster, an electric guitar, light bulb, etc.

8. A bus engine transfers _______ energy into ____ so that the bus moves.
Chemical potential (gas) into kinetic (moving bus)

9. According to the law of conservation of energy, the total amount of energy in the universe ____.
Remains constant

10. What is the SI unit for energy?
Joules

11. Mechanical energy is the sum of what types of energy
Mechanical energy is the sum of what types of energy? Give an example of an object’s mechanical energy. You may illustrate and label or explain.
the total amount of potential and kinetic energy in a system; a child on a swing or a ball being thrown

12. If an apple falls from a tree what can be said about the potential energy, kinetic energy, and its mechanical energy in relation to each other?
Mechanical energy will remain constant; there is a conversion from initial GPE to KE as the apple falls, then KE to PE as the apple lands.

13. What is nuclear fusion? Where does it occur?
a small amount of mass is transformed into a tremendous amount of energy when the nuclei of atoms combine; the sun and stars

14. When you move your hand what type of energy change occurs?
Chemical potential to kinetic

15. When you rub two sticks together this type of energy change occurs? Why?
Kinetic energy to thermal energy; friction

16. What unit is used to tell us how much energy we get from foods?
Calories

17. Define energy.
the ability to cause change

18. A hammer falls off a roof top and strikes the ground with a certain kinetic energy. If it fell from a roof twice as tall, how would its kinetic energy compare? How would its potential energy be different on the higher versus the lower roof before it fell?  
As it had twice as much GPE, it will also have twice as much KE; more potential on the higher roof

19. Which components of food contain calories
Which components of food contain calories? Which contain the most calories?
Carbohydrates, proteins, and fats; fats contain 9 Calories per gram as opposed to 4 Calories in proteins and carbs

20. Identify a situation where it is possible for a ball to have both kinetic energy and potential energy at the same time? Explain.
A bouncing ball’s ME is continually fluctuating between KE and GPE

21. A ball has 100 J of potential energy when it is on a shelf
A ball has 100 J of potential energy when it is on a shelf. Explain what happens to the potential energy and the kinetic energy as the ball falls. Explain what happens to ME.
GPE decreases as it converts to increasing KE ME remains constant

22. A dump truck, a sports car, and a bicycle are traveling at the same velocity. Compare their kinetic energies.
The dump truck has the most mass, so the most KE because velocity is not a factor. The bicycle would have the least KE for the same reason.

23. What electric conversions occur in a toaster?
Electrical energy to thermal energy and light

24. Which position of the rolling ball has the most potential energy
Which position of the rolling ball has the most potential energy? Most kinetic?
A has the highest PE because of height;
D would have the highest KE

25. When you are on a swing and pumping your legs you continue moving
When you are on a swing and pumping your legs you continue moving. When you stop pumping your legs, you will eventually stop. Explain why. Does this violate the law of conservation of energy? Explain.
Kinetic energy is converted to thermal energy due to air resistance and friction between the swing’s ropes or chains where they connect; it does not violate the Law because energy is not destroyed, it simply changes form

26. Where does the energy that moves through earth’s ecosystems come from?
the sun

27. Why is sunlight important to life on earth?
Source of energy that powers food chains and webs

28. What is thermal energy?
the sum of the kinetic and potential energy of all the particles in an object.

29. How are thermal energy and kinetic energy related?
Kinetic energy is easily converted to thermal energy because of friction; also, as thermal energy increases, the kinetic energy of particles increase as well

30. The Sun is our local star. Where does the sun’s energy come from
The Sun is our local star. Where does the sun’s energy come from? What type of energy does the sun send to Earth?
Fusion reactions between hydrogen atom nuclei forming helium and releasing radiant energy

31. Describe what chemical energy is
Describe what chemical energy is. What does chemical energy have to do with the process of photosynthesis?
One product of photosynthesis is glucose, which stores large amounts of chemical potential energy

32. What are the starting and ending materials in the process of photosynthesis?
Starting Materials
Converted to
Ending Materials
 carbon dioxide
water
sunlight 
glucose
oxygen

33. How do cells that make up living things release energy?
Cellular respiration releases stored energy from food that is consumed (animals) or produced (plants)

34. The sun provides energy to producers and the energy flows through the ecosystem in food chains and food webs. Describe both.
Food chain- energy flows from producers to various levels of consumers
Food web- links various food chains in an ecosystem