SECTION
POWER IS THE RATE AT WHICH WORK IS DONE.
4.3 Reading Study Guide B
BIG IDEA Energy
KEY CONCEPT
is transferred when a force moves an object.
Power is the rate at which work is done.
Review
Mechanical energy is a combination of kinetic and potential energy.
Take Notes
I.
Power can be calculated from work and time. (p. 130)
1.
Fill in the frame-game diagram with a definition and examples for power.
POWER
2.
Fill in the main-idea web with terms and details about how power can be
calculated from work and time.
Power can be calculated
from work and time.
CHAPTER 4
Work and Energy
Copyright © by McDougal Littell, a division of Houghton Mifflin Company
A. Calculating Power from Work (p. 131)
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3.
Car A has a motor with twice as much power as Car B. Does this mean that
Car A can travel twice as far as Car B? Why or why not?
4.
What is the formula for calculating power from work? What is the unit of
measurement for power?
5.
A child uses 11 J of energy to pull a wagon for 15 s. How much power has the
child used to pull the wagon?
B. Horsepower (p. 132)
What is horsepower?
II. Power can be calculated from energy and time. (p. 133)
7.
How is power related to energy and time?
A. Calculating Power from Energy (p. 133)
8.
How many joules of energy does a 100-watt bulb require each second?
CHAPTER 4
Work and Energy
B. Everyday Power (p. 135)
9.
Describe what happens at each numbered section of
the diagram.
2
3
4
1:
2:
3:
Copyright © by McDougal Littell, a division of Houghton Mifflin Company
6.
1
248 MOTION AND FORCES, CHAPTER 4, READING STUDY GUIDE B
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