Pendulum period and mass
The bob on a simple pendulum is replaced with one twice as heavy, with the length unchanged. What happens to the period?
Answer A: explanation for every choice
A
Correct. T = 2π√(L/g), which doesn't depend on mass.
B
Mass doesn't appear in the period formula.
C
Mass doesn't appear in the period formula.
D
A √2 increase would come from doubling the length, not the mass.
TakeawayPendulum: T = 2π√(L/g). Mass doesn't matter, but length does.
Equation usedPendulum period
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