Simple and Compound Machines

What is the definition of work?

• A job that completes a task

• Energy transferred when a force makes an object move

• Earning money

If you push against an object and it doesn't move, are you doing work?

• No

• Yes

In order for work to be done, what two things need to happen?

• Object needs to move in any direction

• Object needs to have acceleration and speed

• Object must move and must move in the direction of the force applied

A ___________ is a device that changes the force or increases the motion from work.

• Work

• Job

• Machine

A _________ does work with just one movement of the machine.

• Compound Machine

• Simple Machine

• Useful Machine

A __________ is a combination of two or more simple machines

• Simple Machine

• Compound Machine

• Efficient Machine

Which is an example of a simple machine.

• Pulley

• Bicycle

• Knife

Which is an example of a compound machine.

• Knife

• Pair of Scissors

• Doorknob

What is the SI unit for work?

• Newtons

• Joules

• Grams

a couch is pushed with a horizontal force of 80 N and moves a distance of 5 m across the floor. How much work is done on the moving couch?

• 16 J

• 200 J

• 400 J