Download 1. Define Kinetic NRG. 2. Define Gravitational Potential NRG. 3

1.
Define Kinetic NRG.
2.
Define Gravitational Potential NRG.
3.
Define reference level.
4.
What is the equation for finding the kinetic energy of a body?
5.
What is the equation for finding the gravitational potential energy of a body?
6.
What are the units used for kinetic energy?
7.
What are the units used for potential energy?
8.
What are the units used for mass?
9.
Define Work.
10.
Define Power.
11.
What are the units for Work?
12.
What are the units for Power?
13.
What is the equation for Work?
14.
What is the equation for Power?
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15.
Jim carries a box across the room. Does he do work carrying the box? Why?
16.
Tim pulls on a cart with a force of 60 N for a distance of 5 m. How much work is done by Tim?
17.
Dennis has a weight of 140 N and climbs 6 steps to a height of 6 m. How much work was done by Dennis?
Scott drags a bag of coal 6 m while applying 50 N of force in 18.
30 s. How much power did he produce?
Alan does 4000 J of work running the 40 meter dash. He 19.
completes the dash in 11 s. What power did he produce?
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Jeff has a mass of 50 kg and is standing 20 m above the ground. 20.
a.Find his gravitational potential NRG.
b.Jeff is now standing on the ground. Find his gravitational potential NRG.
c.Find the change in gravitational potential energy for Jeff if he started at 20 m above the ground and ended at ground level. d.Was the change in gravitational potential NRG positive or negative? Why was it so? Explain.
e.What gravitational potential NRG would Jeff have when he is 10 m above the ground?
Jason is running along the street. He has a mass of 45 kg.
21.
a.Find the KE Jason has if he is traveling at 2 m/s.
b.Find the KE Jason has if he is now traveling at 4 m/s.
c.Find the change in KE for Jason.
d.How much was the increase in speed for Jason?
four times
three times
Two times
e.How much did the kinetic energy increase by?
four times
three times
Two times
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22.State the Law of Conservation of NRG.
23.What is an example of an outside force that can make the energy not constant for a system?
24. For a closed system, what does the Law of Conservation of NRG say for KE + PE?
25.Complete the chart for the roller coaster cart at each of the points.
A
D
B
C
E
Position
h (m)
PE (J)
KE (J)
A
100 800000
3000
B
50 C
20 D
E
TME (J)
403000
160000
400000
0 0
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25. continued
a.
What is constant throughout the trip?
b.
At which point is the cart moving the fastest?
Is the cart moving at point A? Explain how you know using c.
the data in the table.
How are points B and D related to each other? What is the d.
same for each point? What is different for each point?
25. continued
e. Find the speed of the cart at point E.
f. Find the Speed of the cart at point C.
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26. Answer the following questions for the skateboarder in the diagram below. The skateboarder starts at rest from point A.
a. If there is no friction present, will the skateboarder make it up the ramp on the other side to point E?
b. At which points on the ramp will the skateboarder have a minimum kinetic energy?
c. At which points on the ramp will the skateboarder have a minimum potential energy?
d. At which point will the skateboarder have a greater kinetic energy, B or D? Explain why.
e. At which point will the skateboarder have a greater potential energy, B or D? Explain why.
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