Compound Pulley

This setup is a compound pulley, which combine both fixed and moveable pulleys to increase the mechanical advantage.

In a pulley system, a wheel's job is to let the rope move freely. Here, this set up works with no wheels. The broom can act as the wheel since it's low-friction enough that the rope can easily move over it.

  1. Ages: 9 - 16

  2. <30 minutes

  3. A little messy

Step-by-step tutorial

  • Step 1

    Set the broom between two chairs or tables and place the jug underneath.

  • Step 2

    Tie one end of the rope to the broom.

  • Step 3

    Thread the rope through the jug handle, then bring it over the broom.

  • Step 4

    Pull down on the rope to lift the jug. How hard do you have to pull?

  • Done!

    Then bring the rope through the jug handle and over the broom one more time. How hard do you have to pull to lift the jug now?

Share what you made & tag us at!