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प्रश्न
Velocity versus time graph of a ball of mass 50 g rolling on a concrete floor is shown in Fig. 9.1. Calculate the acceleration and frictional force of the floor on the ball.
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उत्तर
From the given velocity − time graph, acceleration of the bll,
a = `("Change in velocity")/("Change in time")`
= `(0 - 80)/(8 - 0) "ms"^-2`
= −10 ms−2
Frictional force of the floor o the ball = m
= (0.05 × 10) N (∵ m = 50g = 0.05 kg)
= 0.5 N
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