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Question
Let θ denote the angular displacement of a simple pendulum oscillating in a vertical plane. If the mass of the bob is m, the tension is the string is mg cos θ
Options
always
never
at the extreme positions
at the mean position.
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Solution
at the extreme positions
Tension is the string , \[\text{T} = \frac{\text{mv}^2}{\text{r}} - \text{mg}\cos\theta\]
When v = 0,
\[\left| \text{T} \right| = \text{mg}\cos\theta\]
That is, at the extreme positions, the tension is the string is mgcosθ.
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