Work, Power and Mechanical Advantage

How is work defined?

• the amount of energy 
• the transfer of force over a distance
• rate of work in a given time
• the change in distance in a given time

What is the equation for force?

• F= mass × acceleration
• F = mass × distance
• F= distance/time
• F = mass/time 

What is the unit of measurement for work?

• Newtons
• Joules 
• Watts
• Meters

If a student uses 10 Newtons of Force to push a chair 5 meters, how much is work is being done?

• 2 Joules
• .5 Joules
• 50 Joules
• 20 Newtons

Is this an example of work?
A teacher applies a force to a wall and becomes exhausted.

• True
• False

Is this an example of work? 
A waiter carries a tray full of meals above his head by one arm straight across the room at constant speed. 

• True
• False

What is effort (input) force?

• the force one exerts on a machine

• the force which an effort force must overcome in order to do work on an object via a simple machine.

• the force the machine exerts on a object

• the output work times the input distance

A machine's __________________ is the number of times the machine multiplies the input force.

• power
• force
• mechanical advantage
• efficiency

Which of these is a measurement of power?

• 100 joules
• 100 watts
• 100 meters per second
• 100 hertz

What is the equation for calculating power?

• distance / time
• work x time
• work / time
• force x distance