Work and Power Test Review

Work is considered to be accomplished when... *

• you apply a force to an object.

• an object is moving after you apply a force to it.

• you exert a force that moves an object in the same direction of the force.

The work output of a machine is always less than the work input because...

• All machines have a mechanical advantage.

• Some of the work done is used to overcome friction.

• The machine cannot work as hard as a person.

What unit is used for work?

• Joule

• Newton

• Watt

How does power relate to work?

• Power is the total amount of work done.

• Power is the rate at which work is done.

• Power is the total amount of energy consumed.

Tags

NGSS.MS-PS3-5

A wheelbarrow full of concrete mix that needs to be moved onto a platform could be moved either by lifting it above the ground and setting it onto the platform, or by using an inclined plane. The advantage of using the inclined plane is that the work can be done...

• more quickly.

• with less friction.

• using less force.

• using more energy.

Tags

NGSS.MS-ETS1-1

NGSS.MS-ETS1-2

How does the concept of work done relate to the distance an object moves be calculated?

• work = force x distance

• work = force / distance

• work = distance / force

Tags

NGSS.MS-PS3-5

In which situation is a person doing work on an object?

• A school crossing guard raises a stop sign that weighs 10 N.

• A student walks 1 m/s while wearing a backpack that weighs 15 N.

• A man exerts a 350 N force on a rope attached to a house.

• A worker holds a box 1 m off the floor.

What is the unit used for power?

• Newton

• Gram

• Watt

A simple machine is a fundamental device that makes work easier by changing the___**____of a force used to do the work.

• time or swiftness
• energy or progress

• direction or amount

A man applies a force of 500 N to push a truck 10 m down the street. How much work has been done?

• 50 J

• 500 J

• 510 J

• 5,000 J