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प्रश्न
A simple pendulum having a bob of mass m is suspended from the ceiling of a car used in a stunt film shooting. the car moves up along an inclined cliff at a speed v and makes a jump to leave the cliff and lands at some distance. Let R be the maximum height of the car from the top of the cliff. The tension in the string when the car is in air is
विकल्प
mg
\[\text{ mg} - \frac{\text{mv}^2}{\text{R}}\]
\[\text{mg} + \frac{\text{mv}^2}{\text{R}}\]
zero.
उत्तर
zero
When the car is in air, the acceleration of bob and car is same. Hence, the tension in the string will be zero.
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