Chapter 5 Work and Power

The rate at which work is done.

• Joules
• Power
• Watts
• Newtons

All of the following are examples of a force except.

• A tow truck moving another car.
• Getting pushed on a swing.
• Watching a movie
• Pulling a flag up the flag pole.

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NGSS.3-PS2-1

Which of these is an example of work being done on an object?

• Holding a heavy pieve of wood at a construction site.
• Trying to push a car that doesn't move out of deep snow. 
• Pushing a child on a swing.
• Holding a door shut on a windy day so it doesn't blow open.

For work to be done on an object,

• Some force need only be exerted on the object.
• The object must move some distance as a result of a force.
• The object must move, whether or not a force is exerted on it.
• The object must not move.

In order to do work on an object, the force you exert must be...

• The maximum amount of force you are able to exert.
• In the same direction as the object's motion.
• In a direction opposite to Earth's gravitational force.
• quick and deliberate.

If you exert a force of 20 newtons to push a desk 10 meters, how much work do you do on the desk?

• 200 joules
• 30 joules
• 10 joules
• 100 joules

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NGSS.HS-PS3-1

The net force of any balance force will always be

• >0
• <0
• =0
• Depends on the input force.

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NGSS.HS-PS2-1

The formula for calculating work is...

• work=
  force x distance
• work=
  force/distance
• work=
  newtons x meters
• work = newtons/metwers

If a tow truck does 1000 J of work in 5 seconds then what is the power being used?

• 200 n
• 2000 w
• 2000 n
• 200 w

You push on a desk with a force of 120 N to the right. Your friend pushes on the same desk with a force of 90 N to the left. What is the net force on the desk?

• 0 N
• 30 N
• 210 N
• 65 N

Tags

NGSS.MS-PS2-2