Aman pulls a bucket of water from a meter-deep well, if the mass of rope is m and the mass of the bucket with water is M, then work one by man is
Correct answer: D. (M+m)gh
- A. (M/2+m)gh
- B. (M+m)gh/2
- C. (M+ m/2)gh
- D. (M+m)gh
Explanation
Option D is correct since work done by man will be equal to the gravitational potential energy gained by bucket and rope. Therefore substituting the masses into the formula of g.p.e=mgh gives (M+m)gh.Option A is incorrect since it does not give the correct calculation of masses.Option B is incorrect since it does not give the correct formula.Option C is incorrect since it does not give the correct calculation of masses.
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About Work
Work is done when a force produces displacement, with its value determined by the component of force along the displacement. The topic covers positive, negative and zero work, work by variable forces from force-displacement graphs, and the connection between net work and change in kinetic energy.
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