The special tool you use to make bubbles is called a “Bubble Wand”. Bubble Wands come in all shapes and sizes but no matter what 2-dimensional shape you make your wand, the bubbles will come out round like a ball (sphere). But what if we make a 3-dimensional bubble wand? Can we make a bubble that is a different shape? Time to find out!
You will need:
- A washing up bowl
- Measuring jug
- Washing up liquid (any brand)
- At least 4 metres of medium thickness aluminium wire (can be found in most craft or DIY stores – Hobbycraft, Wilkos etc.)
- Pliers for cutting/bending the wire (adult supervision may be required)
- Glycerin for bubble mixture (optional)
Method – Bubble Mixture:
- Fill your washing up bowl with water (most washing up bowls hold around 5 litres of liquid)
- For every 1 litre of water, add 70ml of washing up liquid.
- Mix gently, try not to let lots of bubbles form on the surface of the mixture.
- Optional – Once the washing up liquid has been mixed in, add 15ml of Glycerin for every litre of water (Results are best if the Glycerin-bubble mixture is left overnight)
Method – Bubble Wands:
- Get your grown up to cut the wire into the appropriate length using the pliers
- Bend one piece of wire into a 3-dimensional triangle (tetrahedron)
- Bend the other piece of wire into a 3-dimensional square (cube)
- Fun Science Tip! – Make sure your 3-dimensional bubble wands are small enough to be fully submerged in the bubble mix.
- If you have leftover wire, try making other 2-dimensional or 3-dimensional bubbles wands.
The Experiment:
- Submerge your tetrahedron bubble wand into the bubble mix and then take it out. You will see the bubble mixture meets in the centre of the wand, creating a strange geometric shape!
- Now try with your cube bubble wand… The bubble mixture meets in the centre of the wand just like before, but this time there is a flat square in the middle!
- You can try blowing a bubble into the centre of your cube bubble wand to create a smaller cube!
The Science Bit:
The bubble mixture wants to pull together tight and get as small as possible, scientists call this Surface Tension. When you blow a bubble, the bubble mixture pulls together around the air inside the bubble and the smallest shape it can pull itself into is a sphere. That’s why all 2-dimensional bubble wands make bubbles that are spheres.
When we use a 3-dimensional bubble wand and don’t let any air inside the bubble, the surface tension of the bubble mixture pulls tight into a different shape because a sphere is not the smallest shape possible.