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प्रश्न
A block of mass 2 kg kept at rest on an inclined plane of inclination 37° is pulled up the plane by applying a constant force of 20 N parallel to the incline. The force acts for one second. Find the kinetic energy of the block at the instant the force ceases to act. Take g = 10 m/s2.
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उत्तर
\[\ nu = \text{ u + at } \]
\[ = 4 \times 1 = 4 \text{ m/sec } \]
\[\text{ So, K . E . } = \frac{1}{2} \text{ m v } ^2 \]
\[ = \frac{1}{2} \times 2 \times 16 = 16 J\]
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