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Question
Which of the diagrams shown in figure represents variation of total mechanical energy of a pendulum oscillating in air as function of time?
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Solution
Explanation:
When a pendulum oscillates in air, its total mechanical energy decreases continuously in overcoming resistance due to air. Therefore, the total mechanical energy of the pendulum decreases exponentially with time. The variation of E vs t is correctly represented by a curve in which the relation between energy and time is shown.
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