In this experiment from the Let's Find Out crew we have a challenge for everyone at home. It's time for more science fun with RTÉjr and our friends at Science Foundation Ireland.

While looking at the pendulum in a clock, Captain Zoom wonders how it swings over and back.

Watch the show now on RTÉ Player!

After discovering that a pendulum consists of a fixed point, a long connecting bit and a weight at the end, two curious kids show her that a pendulum takes the same time to go over and back, no matter how heavy the weight on it is..

This is where Molly and Doireann come in to help. They are in the playground to see how many swings they can do in just 30 seconds. How will they do? Let's find out through this cool science experiment!

Download the full lesson plan here...

You will need:

  • An outdoor swing
  • A timer
  • A friend
  • Your favourite teddy

What to do:

  1. Start swinging and once you are happy that your swinging is as high as you'd like then stop moving your legs and just let the swing move back and forwards without your help.
  2. Ask your friend to start the timer and to count how many swings you do in 30 seconds. How many swings did you do in that time?
  3. Now swap with your friend and get them to start swinging like you did and then time them for 30 seconds while you count the swings. If possible, try to get them to start from higher up than you - but don’t push them! How many did they get?
  4. Now attach your favourite teddy to the swing and push them to get them started, then leave them to swing for 30 seconds. How many swings did they get?

The science bit

Did you find that all of you had the same amount of swings in one minute? Although that may seem strange, it is a scientific discovery that was first spotted by a famous scientist called Galileo Galilei in the 17th century.

Galileo noticed that things would swing at the same rate or speed regardless of how heavy or light they were, once the length of the string was the same. Just like in your investigation, you and your friend and your teddy swung at the same speed because the length of the swing was kept the same.

Also in this episode
Mark and Amy show Zoom that a pendulum can never swing back to the same point from which it was dropped.
And the whole crew go see a giant pendulum swing at a theme park!

Check out the RTÉ Player to watch the full episode HERE and all the series so far HERE!!

AND there are lots more experiments with videos and full instructions - Just click HERE!