Revision Sheet - Nour Al Maaref International School

2nd Term Final
Revision Sheet
 Students Name: __________________________________________
 Grade: 9 A/B
 Subject: Physics
Teacher Signature
_________________
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PHYSICS WORKSHEET
GRADE: 9
MULTIPLE CHOICES
In the space provided, write the letter of the term or phrase that best completes each
statement or best answers each question.
______ 1. Which of the following formulas would be used to directly calculate the kinetic
energy of a mass bouncing up and down on a spring?
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a. KE  k x2
c. KE  1 mv 2
2
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b. KE   1 k x2
d. KE   1 mv 2
2
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 2. Which of the following equations expresses the work-kinetic energy theorem?
______
a. MEi = MEf
c. W = KE
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b. Wnet = PE
d. Wnet = KE
_____ 3. A worker does 25 J of work lifting a bucket, then sets the bucket back down in the
same place. What is the total net work done on the bucket?
a. 25 J
c. 25 J
b. 0 J
d. 50 J
_____ 4. A 3.00 kg toy falls from a height of 1.00 m. What will the kinetic energy of the
toy be just before the toy hits the ground? (Assume no air resistance and that g =
9.81 m/s2.)
a. 98.0 J
c. 29.4 J
b. 0.98 J
d. 294 J
_____ 5. Which of the following is true of the conservation of energy in a closedsystem?
a. Kinetic energy is always conserved.
b. Potential energy is always conserved.
c. Mechanical energy is always conserved.
d. Total energy is always conserved.
_____ 6. The mechanical energy of a system of objects is
a. the sum of kinetic energy and gravitational potential energy.
b. the sum of kinetic energy and elastic potential energy.
c. the sum of kinetic energy and all relevant forms of potential energy.
d. the sum of all forms of energy.
_____ 7. Mechanical energy is not conserved when
a. gravitational potential energy is converted to kinetic energy.
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b. kinetic energy is converted to gravitational potential energy.
c. kinetic energy is converted to elastic potential energy.
d. friction is not negligible.
_____ 8. In which of the following situations is mechanical energy most likely to be conserved?
a. A football flies through the air.
b. A feather falls from the sky.
c. A skateboard rolls into the grass.
d. A hockey player digs his skates into the ice.
_____ 9. If mechanical energy is conserved in a system, the energy at any point in time can be
in the form of
a. kinetic energy.
b. gravitational potential energy.
c. elastic potential energy.
d. all of the above
_____ 10. Which of the following is not a form of mechanical energy?
a. kinetic energy
b. chemical potential energy
c. gravitational potential energy
d. elastic potential energy
______11. Which of the following refers to the rate at which energy is transferred?
a. work
b. kinetic energy c. mechanical energy
d. power
_____ 12. Which of the following refers to the rate at which work is done?
a.energy
b. kinetic energy c. mechanical energy
d. power
_____ 13. Which of the following is not a valid equation for power?
a.P = W /∆t
b. P = Fd /∆t
c. P = Fv /∆t
d. P = Fv
_____ 14. The SI unit for power is
a. N•m.
b. J.
c. W.
d. hp.
_____ 15. How much work can a motor with a power output of 25 W do in 1 s?
a. 1 /25 J
b. 1 J
c. 25 J
d. 25 W
_____ 16. If a machine increases the distance over which work is done,
a. the force required to do the work is less.
b. the force required to do the work is greater.
c. the force required to do the work is the same.
d. the amount of work done is increased.
_____ 17. If a machine decreases the distance over which work is done,
a. the force the machine applies is less.
b. the force the machine applies is greater.
c. the force the machine applies is the same.
d. the amount of work done is decreased.
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SHORT ANSWER
18. Write an equation that expresses the conservation of mechanical energy in a system that
involves kinetic energy, gravitational potential energy.
19. State, in words, the work-kinetic energy theorem.
20. Describe the relationship between energy, time, and power.
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21. What form of energy is associated with the position of an object in Earth’s gravitational
field?
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22. Describe the relationship between kinetic energy and gravitational potential energy
during the free fall of a pencil from a desk.
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23. A car travels at a speed of 25 m/s on a flat stretch of road. The driver must maintain
pressure on the accelerator to keep the car moving at this speed. What is the net work done
on the car over a distance of 250 m?
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PROBLEM
1.What is the average power output of a weightlifter who can lift 250 kg a height of 2.0 m in 2.0
s?
2. What is the kinetic energy of a 0.135 kg baseball thrown at 40.0 m/s?
3. What is the potential energy of a 1.0 kg mass 1.0 m above the ground?
4. What is the kinetic energy of a 1.5  103 kg car traveling at 25 m/s?
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5. An 80.0 kg climber climbs to the top of Mount Everest, which has a peak height of 8848 m.
What is the climber’s potential energy with respect to sea level?
6. An engine uses 29 kN of force to power a car at an average speed of 7.5 m/s. What is the
average power output of the engine?
7. The most powerful ice breaker in the world was built in the former Soviet Union. The ship is
almost 150 m long, and its nuclear engine generates 56 MW of power. How much work can
this engine do in 1.0 h?
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