An engine accelerates a car of mass 800 kg to a speed of $72{\rm{\;km}}{{\rm{h}}^{ - 1}}$. If the frictional force is 10 M per ton, the power developed by the engine is

JEE PHYSICS MCQ: WORK-ENERGY-POWER

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An engine accelerates a car of mass 800 kg to a speed of

72\mathrm{\;km}{\mathrm{h}^{ - 1}}

. If the frictional force is 10 M per ton, the power developed by the engine is

View answer and explanation

Correct option: D

5 kW

Option D (5 kW) is correct because the power developed by the engine is calculated using the kinetic energy and the time taken to reach the final speed, considering the frictional force.

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