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A simple pendulum of length l is pulled ...

A simple pendulum of length l is pulled aside to make an angle `theta` with the vertical. Find the magnitude of the torque of the weight w of the bob about the point of suspension. When is the torque zero?

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The correct Answer is:
A, B
A simple pendulum of length l is suspended from a rigid support. A bob of weight W is hanging on the other point. When the bob is at an angle `theta` wilth the vertical then total torque acting on the point of suspension.
`tau=Fxxr`
`rarr tau=omegarsintheta=omegalsintheta` As the lowest point of suspension the torque will be zero the force acting on the body passes through the point of suspension
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Knowledge Check

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    `1/4 sigma omega pi BR^(4)`

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    A
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