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प्रश्न
A block of mass 5.0 kg slides down an incline of inclination 30° and length 10 m. Find the work done by the force of gravity.
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उत्तर
\[\text{ Mass of the block, M = 5 kg }\]
\[\text{ Angle of inclination } , \theta = 30^\circ\]
Gravitational force acting on the block,
\[ = 10 \times \frac{1}{2} = 5 m\]
\[\therefore \text{ Work done by the force of gravity, w = mgh } \]
\[ = 5 \times 9 . 8 \times 5 = 245 J\]
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