Work

Which of the following is a true statement about work?

• It measures how quickly an object accelerates 
• It measures how much effort is applied over a certain distance
• It measures the change in an object's rate of speed
• It measures how much time it takes to move a massive object

What does one newton exerted over a distance of one meter equal?

• One watt
• One hertz
• One volt 
• One joule 

Tags

NGSS.HS-PS3-1

A kid applies a force of 70 N to a ball over 1.1 meters. How much work did he do on the ball? 

• 77 J
• 7.7 J 
• 0.7 J 
• 770 J 

Tags

NGSS.HS-PS3-2

A weightlifter lifts two 300 newton weights 1.5 meters off the ground. How much work has he done?

• 600 J 
• 660 J
• 900 J 
• 1200 J 

Tags

NGSS.HS-PS3-1

Which of these is a measure of force?

• 100 newtons
• 100 meters per second
• 100 joules
• 100 watts

Tags

NGSS.HS-PS2-1

You move a 12-newton box up a 6-meter ramp. How much work was done?

• 2 J

• 0.5 J

• 60 J

• 72 J

A weightlifter is holding a barbell over her head. In this instance is she doing work on the barbell?

• Yes

• No

Answer explanation

In order for work to be done, the object has to me moving.

A new conveyor system at the local packaging plant will utilize a motor-powered mechanical arm to exert an average force of 890 N to push a large boxes a distance of 12 meters. How much work is done if it pushes 10 boxes?

• 106800 J

• 10680 J

• 74.17 J

• 741.7 J

A 20 kg box is dropped 13 meters. How much work is done on the box?

HINT: To find the force, use F = ma where a is the acceleration due to gravity, 9.8 m/s²

• 196 J

• 2548 J

• 15.1 J

• 260 J

Answer explanation

F = ma

F = 20 (9.8)

F = 196N

W = Fd

W = 196 x 13

W = 2548 J

A cat knocks a 0.01kg toy mouse across the floor with 3N of force. If the cat did 12J of work, how far did the mouse travel?

• 4 m

• 36 m

• 0.3 m

• 0.12 m

Answer explanation

Use the triangle...to find distance, divide work by force so 12 divided by 3 = 4 meters. The mass of the toy is irrelevant, extra information you don't need to answer the question.