Work and Energy

A major league pitcher can throw a baseball with a kinetic energy of 150 J. How much work must the pitcher do to the ball to give it that much KE?

• 50 J

• 0

• 150 J

• 300 J

Tags

NGSS.HS-PS3-1

Which requires more work: a person walking up stairs or a person running up stairs?

• walking

• running

• they require equal work

• no work is required for either because the movement is vertical

Each of the boxes shown is pulled for 10 m across a level, friction less floor by the force given. Which box experiences the greatest change in its kinetic energy?

• A

• B

• C

• D

• E

When the velocity triples, the kinetic energy increases by ______ times.

• 9

• 3

• 1.5

• 4.5

The work-kinetic energy theorem says that the net work done by all the forces acting on an object is equal to the change in the ………. of the object.

• mechanical energy

• work

• momentum

• kinetic energy

A 10.0 kg box is accelerated from 2.0 m/s to 4.0 m/s. What will be the work done?

• 50 J

• 60 J

• 20 J

• 45 J

What does work equal when the final change in kinetic energy equals 20,000 J?

• 0 J

• 20,000 J

• 2041 J

• 4164931 J

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

On a force versus position graph, the area under the curve is a representation of:

• Force

• Kinetic Energy

• Potential Energy

• Work

Which situation is work not done?

• lifting a 20 pound box off the floor

• holding a 20 pound box above the floor

• sliding a 20 pound box across the floor

• sliding a 20 pound box up an inclined plane