Have you ever tried to balance on a beam or the kerb of a pavement before? You probably had to keep your arms out like this so that you don't fall off.

Having your arms like this helps you to balance because it slows down your wobbling and gives you more time to get your balance back.

We fall off things because we lose balance and gravity sends us back down to the ground. But what lets us balance in the first place?

Well, everything has a centre of gravity. This is the point at which things usually balance well.

Kate was able to balance this metre ruler on her finger because the centre of gravity is right in the middle. But when she moves her finger, the weight becomes unevenly distributed and so, it falls.

The lower down the centre of gravity, the more stable it is. This toy is difficult to knock over because it has a weight inside, at the bottom.

A human's centre of gravity is about here - just above the belly button.

That's quite high up which is why it makes it difficult to balance on a tightrope. Fearne had a try...

...but soon fell off!

So how do people manage stay on? This can help. It's a pole with a weight on either end, which lowers your centre of gravity and makes it easier to balance.

Adding extra weight to either end - in this case, bags of sugar - makes the pole bend even more so that the centre of gravity is below the wire, making it much more difficult to fall off.

Success! As you can see, both ends of the pole are lower than the wire giving Kate a much better balance.

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