### DRW Ch. 5 Sec. 1 - Keller ISD Schools

```Name _______________________________________________ Date ________________ Class______________
CHAPTER
5
Work and Machines
following questions.
“One, Two . . . Stroke!”
(p. 110)
1. What makes the Dragon boats move?
have a chance to revise your answers based on what you’ve learned.
Start-Up Activity (p. 111)
CHAPTER 5
3. What is the purpose of this activity?
Section 1: Work and Power
(p. 112)
▼
▼
▼
2. What is this team doing as they compete in Hong Kong’s Dragon
Boat Races?
this question. True or False? (Circle one.)
TEXAS EDITION, GRADE 7, UNIT 2 RESOURCES
15
Name _______________________________________________ Date ________________ Class______________
The Scientific Meaning of Work (p. 112)
5. When you bowl, you are applying a
to the bowling ball that makes it move a certain distance.
6. When you are carrying a heavy suitcase at a constant speed, you
are not doing work. Why not?
7. Look at Figure 3. Which of the following is having work done on
it? (Circle all that apply.)
a.
b.
c.
d.
a
a
a
a
carton as you push it at a constant speed
backpack as you walk at a constant speed
grocery bag as you pick it up
grocery bag as you carry it at a constant speed
applied to the object and d is the
through which the force is applied.
9. Suppose you want to calculate how much work it takes to lift a
160 N barbell. Besides the weight of the barbell, what other information do you need to know?
a.
b.
c.
d.
the shape of the weights
how high the barbell is being lifted
the strength of the person doing the lifting
none of the above
Power—How Fast Work Is Done
10. The
power.
(p. 115)
is the unit used to express
11. If you increase power, you are increasing the amount of work
done in a given amount of time. True or False? (Circle one.)
Section Review (p. 115)
Now that you’ve finished Section 1, review what you learned by