Simple Machines

How does an axle and wheel help someone to work?

• It transfers force from one wheel to the other.
• It makes heavy objects lighter
• It uses an inclined plane.
• It eliminates friction.

A pulley has 8 pounds of weight on it's load along with 4 lines of string wrapped around it (compound pulley). In order to lift the load using as little force as possible, how much force is needed to lift the pulley?

• 32 pounds worth of force
• 8 pounds worth of force
• 2 pounds worth of force
• 4 pounds worth of force

change of direction

• change in force
• change in direction
• change in distance
• it splits

How is an inclined plane used in a screw?

• The inclined plane is only shown on the head of a screw
• The inclined plane is wrapped around a cylinder in a screw
• The inclined plane in the screw is the long, middle beam that holds the thread
• An inclined plane is not used in a screw

How many class levers are there?

• 2
• 3
• 4
• 5

Which of these is NOT an example of a wheel and axle?

• steering wheel
• door knob
• light switch
• water faucet handle

What makes it easier for you to use less force when pulling on a pulley

• Move strings
• more pulleys
• duh...make someone else do it
• more people

Which is NOT a use of a pulley?

• Decrease friction
• Lift things to where you can't reach
• Measure how heavy a load is
• Pull things down

If you used one pulley to lift a 1000 grams, then used two pulleys to lift the same 1000 grams and the work became 500 pounds easier to lift, how much easier would the work become if you used three pulleys to lift the 1000 pounds?

• 800 lbs easier
• 600 lbs easier
• 700 lbs easier
• wouldn't change

What is an inclined plane?

• a ramp that assists moving heavy objects up and down ramps
• helps bring objects up and down using a wheel and rope
• uses a fulcrum and a plane to lift things
• used to split load