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Question
A pendulum clock gives correct time at the equator. Will it gain time or loose time as it is taken to the poles?
Solution
According to the relation : \[T = 2\pi\sqrt{\frac{l}{g}}\] The time period (T) of the pendulum becomes proportional to the square root of inverse of g if the length of the pendulum is kept constant.
i.e. \[T \propto \sqrt{\frac{1}{g}}\]
Also, acceleration due to gravity (g) at the poles is more than that at equator. Therefore, the time period decreases and the clock gains time.
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