Pendulum Animation

Play with a pendulum:

This is a good example of a mathematical model. Each unit of time is calculated using the data from the previous unit of time, and the motion you see is the result.

For example the period is timed from top to bottom (not an in-built formula) so it can take a short while to find a value, and can vary a little due to calculation accuracy.

What are PE and KE?

The KE and PE are constantly calculated and you can see that their total stays the same (apart from slight changes due to rounding).

Why is the total constant? Because one type of energy is converted to the other and back again.

It is really cool how this works!

Notice how PE is highest at the top of the swing and zero at the bottom.

And KE is highest when the pendulum swings the fastest (at the bottom of the arc).

Use pause to look at the values.

There is no friction or drag in this model, so the pendulum keeps going. In the real world it would slow down.

Things to try: