Pendulum clock

[bill107]

Why is it when you decrease/increase the length of the pendulum the clock runs faster/ slows up ?

[Dassie]

Because the pendulum drives the clock and the shorter it is the less far it has to travel and so it runs faster.

To demonstrate, If you take a length of string and put a heavy weight on the end and then swing it back and forth the shorter the string the faster it goes.

[Teddio]

The time period of the pendulum increases as the length of the pendulum increases, therefore your clock would run slower (and vice-versa). Clock pendula are "compensated" so their length reamins constant as the temperature changes.

[bill107]

Thanks both for your valued help