Energy Study Guide

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Energy Study Guide

This will not be taken up. It is provided as an extra study tool. This guide may not cover every single concept. It is not meant to reflect any actual test questions. It is simply provided as a basic review guide. You need to also review all related PowerPoints and notes that are still in our Google Classroom! (100 pt. gold level test will be Thursday, 11/14)

According to the picture below, at which point has the greatest potential energy? ________Up at the Top_______

According to the picture below what point has the greatest kinetic energy? __________The last Ball____________________

3. In competition, weightlifter 1 lifts a 150 kg weight from the floor 6m above his head. Weightlifter 2 also lifts 150kg weight above his head to 5.5m. How much more energy does weightlifter 1 use than 2?

4. If kinetic energy of a 20kg mass is 160J, what is its speed?

5. What is the kinetic energy of a bicycle with a mass of 25kg traveling at a velocity of 4m/s?

6. Identify whether the following example is potential energy or kinetic energy:

A person on a sled poised at the top of a hill ______________

A steel dam holding back a reservoir of water _____________

A woman swings a golf club _________________

An apple suspended in a tree _______________

An apple falling from a tree _________________

A stretched rubber band____________________

7. The law of conservation of energy states _______________________________________________________________

8. What does gravitational potential energy depend on? __________________________________________________

9. What is kinetic energy? ___________________________________________________________________________

10. What is potential energy? ________________________________________________________________________

11. What is the formula for KE? _______________________________________________________________________

12. What is the formula for PE? _______________________________________________________________________

13. What is the unit for energy?_______________________________________________________________________

14. What is the acceleration rate due to gravity? ___________ (give proper units)

15. What is energy? _________________________________________________________________________________

16. What it the formula for work? ___________________________________________Units?______________________

17. What it the formula for power? __________________________________________Units?______________________

Solve: A person is using a force of 300N to push a cart. How much power does the person need to push the cart a distance of 5m in 20s? P = w/t P = F x d / t P = (300 N) (5 m) / 20 s P = 1500 J / 20s = 750 watts (J/s)

18. What specific type of potential or kinetic energy do the following contain or use? (Refer to diagrams in your GC PP.)

food - __________________________

LED - ___________________________

burning wood - ___________________

Hydrogen bomb - ____________________

e. pendulum of a clock - __________________

f. rubber band - ________________________

g. ball in flight - ________________________

h. stereo - _______________________

i. lamp oil - ________________________ J. computer - _______________________

19. What is elastic potential energy?____________________________________________________________________

20. What is the amount of work done when a force of 10N moves a wagon a distance of 8 meters? ____________How much power does it take if it is done over a 5 sec time period?_______________

21. A force of 15N is used to push a box along the floor of 3 meters. How much work is done?

22. What is the formula for power?_______________

23. How much energy is there in a 50 kg bowling ball, 10 meters off the floor? ____________Assuming no wind resistance or friction, what is the velocity of it when it hits the ground? _________________What is the ball’s kinetic energy when it hits the ground? ______________________What is the ball’s kinetic energy when it is stationary on the shelf? ________________________

24. If a cart is moving at 50 m/s and it takes 3300 J of energy to move it, what is its mass?

25. If the gravity of the moon is ⅙ of the Earth’s gravity (so 1.63 m/s2) and Neil Armstrong has a mass of 100kg, when does Neil have more potential energy - 20 meters above Earth or above the moon?__________ How much more potential energy does he have? (Hint - must calculate PE using g for earth and then for moon.)

26. If a bullet is shot into air 550m and weighs .2kg, what is the bullets potential energy at the top of its flight? Assuming no friction or wind resistance, what is its speed when it hits the ground?

27. Describe all that you can about the energy, work and forces associated with the following pirate ship ride.

Energy of ride Work being done Forces affecting ride

28. Why do you have to occasionally reset a grandfather clock?________________________________

29. Describe the energy transfers / conversions that could / would take place:

Electric energy to a hair dryer - _________________________________________________________

Gasoline combustion in a car - _________________________________________________________

Radiant energy of the sun - ____________________________________________________________

30. Is a roller coaster a perfect PE ↔ KE system? _____ Why or why not?

31. Describe one common way that electricity can be generated.____________________________________