The Wheel and Axle

1
The Wheel and Axle

• Mark-o
• Eric-o

2
What makes it a wheel and axle system?

• The wheel must be fixed to the axle.
• One rotation of the wheel equals one rotation of
  the axle.
• If the wheel and axle are not fixed then you
  basically have a pulley system.

3
Everyday examples of a wheel and axle system

• A doorknob
• Sprocket and shaft
• Fishing reel
• Carousel

4
Whats the point?

• Provides a simple way to obtain Mechanical
  Advantage.
• The example to the right shows a simple system
  with an MA of 51.
• The radius of the wheel in this case is 5x the
  radius of the axle.

5
Wheres the sacrifice?

• As with any system using MA, you give something
  to gain something.
• Here you are increasing the distance that you
  must turn to achieve one rotation of the axle,
  but you are increasing torque at the axle by the
  same ratio, thus making it easier to raise the
  bucket.

6
Find the wheel and axles
7
Drum Diameter Demo (DDD)