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ALCULATING POWER
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Power isthe amount of wOl1<done per unit of time. The unit for power, joules/second,
Work has a special meaning In science. It Isthe product of the force applied to an objec
and the distance the object moves. The unit of work Isthe joule (J).
W
=
Force x Distance
W
=
Fxd
Force = newtons
Distance = meters
the watt.
Power
=
work
time
work
time
Is
= joules
= seconds
SOlvethe foHowing problems.
1. A set of pulleys Is used to lift a plano weighing l,O.Xl newtons. The plano Is lifted
Solve the following problems.
1. A book weighing
3 meters in {JJ seconds. How much power is used?
1.0 newton Is lifted 2 meters. How much work was done?
Answer.
Answer:
2. A force of 15 newtons Isused to push a box along the floor a distance of 3 mefers.
How much work was done?
2. How much power is used if a force of 35 newtons Is used to push a box a distance
of 10 meters in 5 seconds?
Answer.
Answer.
3. It took 50 joules to push a chair 5 meters across fhe floor. With what force was the
chair pushed?
3. What Isthe power of a Idtchen blender If It can perform 3,750 Joules of work In
15 seconds?
Answer:
4. A force of 100 newtons was necessary to 11fta rock. A fofal of 150joules of work was
done. How far was the rock lifted?
Answer:
4. How much work Isdone using a 5QO-watt microwave oven for 5 minutes?
Answer:
5. It took 500 newtons of force to push a car 4 meters. How much work was done?
Answer:
Answer:
5. How much wOl1<Isdone using a 6O-watt light bulb for 1 hour?
-
Answer:
Nome
CAi.COlA. ~;-,jGWORK
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Nom",
CALCULATING POWER
Power Isthe amount of woo done per unit of time. The unit for power, joules/second,
Work has a speclal meaning In science. It is the product of the force applied to an objec
and the distance the object moves. The unit of work Is the joule (J).
the watt.
Power
=
work
lime
W = Force x Distance
=
Force = newtons
Distance = meters
Fxd
= joules
.
= seconds
Solve the foUowlng problems.
1. A set of pulleys Is used to lift a plooo weighing 1,exxl newtons. The plano Is lifted
3 meters In {fJ seconds. How much power is used?
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Solve the following problems.
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.1. A book weighing 1.0 newton Is lifted 2 meters. How much work was done?
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2. A force of 15 newtons Is used to push a box along the floor a ~ance
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of 3 meters.
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ANNier:
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ANNier:
3. What Is the power of a kitchen blender If It can perform 3,750 joules of work In
15 seconds?
ION
4. A force of 100 newtons was necessary to Ufta rock. A total of 150 joules of work was
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2. How much power Is used if a force of 35 newtons Is used to push a box a distance
of 10 meters in 5 seconds?
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3. It took 50 joules to push a chair 5 meters across the floor. WIth what force was the
chair pushed?
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Answer:
How much work was done?
done. How for was the rock lifted?
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work
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ANNIer:
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4. How much work Is done using a 500-watt microwave oven for 5 minutes?
ANNIer:
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5. It took 500 newtons of force to push a car 4 meters. How much work was done?
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ANNier:
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Answer:
5. How much woo Isdone using a 6O-watt light bulb for 1 hour?
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Answer: