Updated: Apr 5, 2020
What is better for small people than the chance to fling things through the air? It brings them so much joy.
Early into our lockdown journey, my 5 year old son designed his own catapult (that's writing practice isn't it?). So we decided to make some and test out how far they could fling things through the air.
This activity gives you the chance to talk about different masses (heavy and light), what "energy" is and how you can change energy from one form to another, and what a trajectory is.
A quick brush up on energy... there are lots of kinds of energy, and it can be transformed from one type to another. Some types of energy are electrical, chemical, sound, light, potential, gravitational and kinetic (movement). We are transforming energy around our homes all the time - we turn on the lights and we turn electrical energy to light energy, we eat food and we turn the chemical energy stored in it into mechanical energy as we move around, we turn on a torch and we turn chemical energy from the battery into light energy. You can also transfer energy from one place to another, such as through the electric wires in the walls, through a charger and into our phone battery.
A catapult only works because you can both transform and transfer energy.
How to make your catapult...
You will need:
- eight paddle-pop sticks
- five rubber bands (although we've gone into lockdown without any so we used hairbands)
- a bottle top
- a few different projectiles of different sizes and weights (pom poms, cotton wool balls, peas - try lots out) NOTE - it is not safe to fire things at people, don't aim the catapult at anyone
Step 1: Take six of the paddle-pop sticks and tie them tightly together at each end with a rubber band (about a cm or two in).
Step 2: Take the other two paddlepop sticks and join them with a rubber band at one end (about 1cm in).
Step 3: Slide the stack of 6 paddlepop sticks between the two you have just joined together, and using another rubber band or two join the two pieces together, in a cross shape.
Step 4: Using the blu-tak stick the bottle top to the open end of the two paddle-pop stick piece.
Step 5: Pop the projectile in the bottle top and using your finger press the end down... then release to transfer the energy into the projectile and fire it through the air.