A steel ball is released from rest a distance above a rigid horizontal surface and bounces several time. The diagram shows how its velocity varies with time. Which statement correctly explains why the areas X and Y are equal?
| A. |
The ball’s acceleration is not same during its upward and downward motion. |
| B. |
The speed at which the ball leaves the surface after an impact is equal to the speed at which it returns to the surface for the next impact. |
| C. |
For one impact, the speed at which the ball hits the surface equals the speed at which its leaves the surface. |
| D. |
The ball rises and falls through the same distance between the impact 1 & 2. |
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