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प्रश्न
A ball is given a speed v on a rough horizontal surface. The ball travels through a distance l on the surface and stops. what are the initial and final kinetic energies of the ball?
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उत्तर
Initial kinetic energy of the ball,
\[K_\text{i} = \frac{1}{2}\text{m v}^2\]
Here, m is the mass of the ball.
The final kinetic of the ball is zero.
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