Let's Find Out features Captain Zoom and her crew of scientists, Amy and Mark, as they seek out new science fun with exciting experiments, curious kids and a trip to a faraway place.

The show is produced with support from Science Foundation Ireland and there's load of great resources for teachers too!

Watch the full show here on RTÉ Player!

Here, Mark needs help lifting Amy’s toolbox so Mark and Amy introduce Zoom to the pulley. Two curious kids show her how compound pulleys can help you lift very heavy things.

You will need:

  • Two small single pulley blocks (can be bought online)
  • 2-metre rope (that fits into the pulley blocks
  • Two small clips
  • A strong bar or stick between two supports
  • A weight for lifting, e.g. a bucket of water

What to do:
1. Try lifting the weight. How hard is it to lift?
2. Attach a pulley to the bar. Thread the rope around the pulley wheel and tie one end of the rope securely to the weight.
3. Pull on the other end of the rope, does that make it easier to lift the weight than it was when you tried without the pulley?
4. Now add a second pulley to the bar. This time, thread the rope through one pulley, around the handle of the weight, through the other pulley and then secure the end of the rope to the weight.
5. Pull the end of the rope. Is it now easier or harder to lift the weight than when you had just one pulley?
6. Did you have to pull more or less rope to lift the weight?

The science bit...

Pulleys are wonderful inventions, they are called a simple machine and they provide us with an advantage when lifting or moving a weight. In this case the pulley makes it easier for us to lift the weight; the more pulleys we use, the easier it is to lift, but we have to pull more rope to do so.

With two pulleys, the weight feels two times lighter but you have to pull two times more rope!

Also in this episode...

Mark and Amy show Zoom how lifts use a pulley and a counterweight to move people between the floors of a building. And the whole crew go see a famous building with lifts that can be seen from outside: the Eiffel Tower!

Click here to see all the experiments from the series!