A Home Brewed Worksheet: Chapter 6 and Coasters
(for my Conceptual Physics students)
6.1 Work-ForceXDistance
1. Work=forceX________, which is a change in
_______.
2. The amount of work done on a body depends on how
much ________ is applied and _______the force
causes the object to move.
3. The unit of work combines the unit of force, which
is the ______, and the unit of distance, which is the
_______. We call a newton-meter the ______.
4. The ability to do work is _______ and its unit is
the ________.
6.2 Power-How Quickly Work Gets Done
5. The equation for finding power is work divided
by______________.
6. What is the unit for power?
Answer: ______________.
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6.3 Mechanical Energy
7. Mechanical energy is either ________energy,
_______ energy, or both.
8. Potential energy is _______ energy that arises
because of an object’s __________.
Kinetic energy is energy of ________ possessed by
________ objects.
9. The unit of energy, whether kinetic or potential, is
the ____________.
6.4 Potential Energy Is Stored Energy
10. Potential energy, PE is found by using the following
equation. FILL IN THE BLANK.
PE=____________
11. Calculate the potential energy of the following
mass. Show your work on the “board”. Include units!!
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12. Knowing that work is the means by which energy is
transferred from one body to another,
a. how much work is done to lift a 1 kg mass 1 meter?
Answer: ___________
b. how much work is needed to push a 1 kg mass up a
hill that is 1 meter high? Answer: ___________
6.5 Kinetic Energy Is Energy of Motion
13. Kinetic energy KE is found by using the following
equation. FILL IN THE BLANK.
KE=____________
14. Calculate the kinetic energy of a 1 kg ball
travelling at 1 m/s. Show your work on the “board”.
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15. Calculate the kinetic energy of a 1 kg ball
travelling at 2 m/s. Show your work on the “board”.
16. By how much does the kinetic energy of a car
increase if its speed doubles? Answer: ___________.
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6.6 Work-Energy Theorem
17. To increase or decrease kinetic energy, work must
be done. The equation which relates work to kinetic
energy is given by:
Work = ____________________
18. Recall that Work=forceXdistance. When a car
applies its brakes, the force of friction doesn’t depend
on speed, so ____________is what varies with speed.
Therefore, a car that is moving twice as fast as
another needs ________ times as much distance to
stop.
19. A car that is moving three times as fast as
another needs ________ times as much distance to
stop.
6.7 Conservation of Energy (and Coasters)
20. A pendulum swings back and forth as shown in Fig.
1. Note the kind of energy (KE or PE or both) the
pendulum has at each location ( A, B, C, and D).
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Fig. 1. A pendulum swinging.
Questions # 21 through # 25 refer to the coaster
shown in Fig. 2 which has a loop. The coaster starts
from rest at point A, is pulled up the hill to point B, and
released to coast without friction.
21. If the coaster has a free-fall curved track at point
E, the riders will feel _____________and the net
force on a 200 pound passenger will be equal to
_____________.
22. If the energy of the coaster at point B consists of
5000 Joules of potential energy and 1000 Joules of
kinetic energy, how much work was done on the coaster
from point A to point B? Assume that the coaster
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starts from rest at point A. Answer: ____________
Joules.
23. When the coaster reaches point C its potential
energy is equal to __________ Joules and its kinetic
energy is equal to _________ Joules.
24. At point D, the top of the loop, the coaster has
both __________ and ___________ energies.
25. At point F and beyond the coaster has only
_______ energy.
Fig. 2. A coaster with a loop.
6.8 Machines-Devices to Multiply Forces
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26. For each of the following pulley systems shown in
Fig. 3 determine the distance needed to lift the 100
pound weight 1 meter.
Fig. 3. Pulley Systems.
27. For pulley system “b” in Fig. 3, determine the
force input required to lift the load.
Answer:____________ pounds.
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