Question
A girl is swining in a sitting position. If it becomes vertical, how will the period of the swing change?
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Answer
Oscillation time of simple pendulum is
$T =2 \pi \sqrt{\frac{l}{g}}$ i.e. $T \propto \sqrt{l}$
When the girl stand up, the distance between the suspension point and the center of mass of the swinging body reduces, that is reduced. This is why the value of T will decrease.
$T =2 \pi \sqrt{\frac{l}{g}}$ i.e. $T \propto \sqrt{l}$
When the girl stand up, the distance between the suspension point and the center of mass of the swinging body reduces, that is reduced. This is why the value of T will decrease.
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