Will a pendulum clock that is accurate at room temperature of 30 degrees gain or lose time when the temperature increases to 40 degrees celsius?

Answer 1

Virtually all solids expand when they get warmer. Especially in the neighborhood of

30° to 40° C, and especially common materials used to construct common household

items.

So the pendulum bar or rod ... (I don't know what it's called but I mean the straight

rigid thing between the pivot and the weight on the end) ... expands when it warms,

and its effective center of mass moves farther from the pivot. This has the effect of

increasing the period of the pendulum, so the clock runs slower, and "loses time".

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