Efficiency and Mechanical Advantage

Efficiency and Mechanical Advantage

Multiple Select

How can machines help you do work?

• Change the amount of force you're using

• Change the amount of work you're doing

• Change the direction of your force

• Change the distance you move something

Multiple Choice

In a real-world machine, what is true about work in compared to work out?

• Work In > Work Out

• Work In = Work Out

• Work In < Work Out

Multiple Choice

You push down on a lever with a force of 100 N to lift a 500 N box.

What is the input force?

• 100 N

• 500 N

Fill in the Blank

You push down on a lever with a force of 100 N to lift a 500 N box.

What is the mechanical advantage of the lever?

Multiple Choice

You have a lever with a mechanical advantage of 5.

What is most likely its ideal mechanical advantage?

• 6

• 5

• 4

Multiple Choice

Is it possible to have a machine in the real world with 110% efficiency?

• Yes

• No

Fill in the Blank

As a percent, what is the efficiency of a machine that puts out 90 J of work when you put in 100 J of work?

Multiple Choice

Which of the following machines loses the most energy to heat?

• 50% efficient machine

• Output Work = 60 J

  Input Work = 100 J

Open Ended

A machine's efficiency can be improved by reducing friction.

What can you do to reduce friction in a machine?