Work, Power, and Efficiency

How much work is done in holding a 15 N sack of potatoes while waiting in line at the grocery store for 3 minutes?

• 15 J
• 45 J
• 0 J
• 5 J

A person weighing 600 N gets on an elevator. The elevator lifts the person 6 m in 10 seconds.  How much power was used?

• 360 W 
• 60 W
• 3600 W
• 600 W

800 Newtons of force moving a distance of 20 meters will be how much work done?

• 40 J
• 1,600 J
• 400 J
• 16,000 J

500 Watts of power took in 90 seconds results in how work was done?

• 45,000 watts
• 45,000 J
• 4,500 J
• 5.55 J

Tags

NGSS.HS-PS3-1

How far does a car that weighs 5,000 N go if 18,000 J of work is done on it?

• 3.8 m
• 3.7 m
• 3.2 m
• 3.6 m

Tags

NGSS.HS-PS3-1

What is power?

• transfer a force through a distance
• the rate of speed 
• the rate of work being done
• transfer of space over time

A Mustang has more horsepower than your mom's minivan. What does this mean?

• The Mustang has a higher topspeed.
• The minivan has a worse gas mileage.
• The Mustang can do work faster.
• The Mustang will die.

Tags

NGSS.HS-PS2-1

NGSS.HS-PS3-3

The efficiency of a machine can be increased by reducing __________________________. 

• effort
• resistance friction
• fulcrum
• friction

The amount of work done in a certain amount of time is known as 

• work
• effort force
• resistance force 
• power

Work is done on an object when the object moves in the SAME direction in which the force is applied.

• True
• False