I should.

This is about coupled pendulums.

This is a bit of string on from the bit of string I've dangled to pendulum going for a cream egg with a little button on the bottom to make sure that it doesn't slip off.

Now then, if I bang one of these pendulum forwards like this, it would eventually stop again.

Look, bang it like that on a later time, it's stationary and then later time it is stationary.

It's magic on.

I remember a magician shyness on a television show, where he put a handkerchief in front to say, Now it's stationary and it would be on.

Then he'd open this one up and say, Now this is stationary and it will be This is magic, only simple laws of physics at work.

We call these coupled oscillators.

The reason is this is one oscillator on.

That's another one, but they're coupled in a funny way through the string at the top.

And there are little forces as this goes out of line that pull from one to the other, transferring energy from this one, which is now coming to arrest here over to that one and then back again.

Have fun for Easter on.

Remember, use hygienic needles if you're going to eat the eggs afterwards.