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प्रश्न
Give scientific reasons.
It is easier to stop a tennis ball as compared to a cricket ball when both are travelling with the same velocity.
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उत्तर
- The momentum of a body is the product of its mass and velocity, i.e., p = mv and the rate of change of momentum of a body is equal to the force applied, i.e., `"F" = ("m"("v" -"u"))/"t"`.
- In the given information, both the balls move with the same velocity and finally stop; thus, the force applied to stop the ball will be directly proportional to the mass of the ball.
F ∝ m - It is easier to stop a tennis ball than a cricket ball moving with the same speed because the momentum of a cricket ball will be higher than that of the tennis ball, as the mass of the cricket ball is more than tennis ball. Therefore, less force is required to stop the tennis ball when compared to the cricket ball.
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