Power Notes

LESSON: POWER

Multiple Choice

What is needed to calculate work?

• time and distance

• speed and distance

• force and direction

• acceleration and velocity

Multiple Choice

What is the unit of measurement for work?

• meters

• newtons

• m/s

• Joules

Multiple Choice

You have to push with 15 N of force to move it 10 meters. How much work do you do?

• 15 Joules

• 150 Joules

• 1.5 Joules

• .67 Joules

Multiple Choice

500 J of work is done by a person who uses a force of 50N to move a box, how far does it go?

• 10 m

• 0.1 m

• 25,000 m

• 10 J

• Power is the rate at which work is done or how much work is done in a certain
amount of time.

• Power is measured in watts.
power = work
time

p = w / t

POWER

​Write this slide in your notbook.

Practice Power Problems

1. While rowing in a race, John does 3960 J of work on the oars in 60.0 s. What is his power output in watts?

​​Work this problem out in your notbook.

Math Response

While rowing in a race, John does 3960 J of work on the oars in 60.0 s. What is his power output in watts?

Type answer here

Correct Answer: 66

Deg^°

Rad

Practice Power Problems

2. Using a jack, a mechanic does 5350 J of work to lift a car .500 m in 50.0 seconds. What is the
mechanic’s power output?

​​​Work this problem out in your notbook.

Math Response

Using a jack, a mechanic does 5350 J of work to lift a car .500 m in 50.0 seconds. What is the
mechanic’s power output?

Type answer here

Correct Answer: 107

Deg^°

Rad

Practice Power Problems

3. Anna walks up the stairs on her way to class. She weighs
565 N and the stairs go up
3.25 m vertically. What is her
power output if she climbs the stairs in 12.6 s?

​​​Work this problem out in your notbook.

Math Response

Anna walks up the stairs on her way to class. She weighs 565 N and the stairs go up
3.25 m vertically. What is her
power output if she climbs the stairs in 12.6 s?

Type answer here

Correct Answer: 145.7

Deg^°

Rad