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प्रश्न
A ball is rolling from A to D on a flat and smooth surface. Its speed is 2 cm/s. On reaching B, it was pushed continuously up to C. On reaching D from C, its speed had become 4 cm/s. It took 2 seconds for it to go from B to C. What is the acceleration of the ball as it goes from B to C?
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उत्तर
The acceleration of the ball between A to B is zero as the speed and direction of the ball are constant. After point B, a force is applied. Thus, the ball will get accelerated.
`"Acceleration of the ball from B to C" = "Change in velocity from B to C"/"Time taken for this change"`
`"Acceleration of the ball from B to C" = (4 - 2)/2 = 1m"/"s^2`
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