MEPX
Chapter 1 of 10All chapters
  1. 1The simple machines
  2. 2Levers and gears
  3. 3Engines
  4. 4Hydraulics and pneumatics
  5. 5Getting power where it is needed
  6. 6Household machines
  7. 7Electric motors and generators
  8. 8Efficiency and losses
  9. 9Why machines fail
  10. 10Working out an unfamiliar machine

Chapter 1 of 10

The simple machines

Six ways to trade force for distance.

The bargain

Lever, wheel and axle, pulley, inclined plane, wedge and screw. Each lets you apply a smaller force over a longer distance to do the same work.

  • Nothing multiplies energy. Mechanical advantage is force multiplied, distance divided.
  • Friction means real machines need slightly more work in than they deliver out.

Recognising them

A ramp is an inclined plane, a screw is a ramp wrapped round a cylinder, an axe is a wedge, and a spanner is a lever. Complex machines are combinations of these six.