Simple Machines

What is an example of a third-class lever?

• broom
• screwdriver
• screw
• wheelbarrow

What kind of lever has a fulcrum, resistance arm, and effort arm?

• 1st Class Lever
• 2nd Class Lever
• 3rd Class Lever
• All of the above

A machine multiplies your effort force by 3 times.  What does the number 3 represent?

• force
• mechanical advantage
• distance
• work

What kind of lever has the fulcrum between the effort and the resistance and changes the direction of a force?

• 1st Class Lever
• 2nd Class Lever
• 3rd Class Lever
• No Class Lever

What is the formula for calculating work?

• F = w/d
• w= f x  d
• d = w/f
• ma = Fr/Fe

What is the metric unit for work?

• meter
• newton
• joule
• miles

What is the fixed point around which a lever is free to turn?

• fulcrum
• resistance
• effort
• lever

A wheelbarrow, pulley, and wedge are all examples of what?

• levers
• inclined planes
• wheel and axel
• simple machines

What is the scientific meaning of work?

• when you get paid
• work happens when an object changes its postion in direction of force
• work happens when an object does not move
• work happens when you think about it

How does a first-class lever affect direction?

• It changes the direction 
• They do not change the direction of force
• The direction is maintained
• the force is changed.