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Class 9
Science
Force and Laws of Motion
two persons manage to push a motorcar of mass 1200...

Question:
Two persons manage to push a motorcar of mass 1200 kg at a uniform velocity along a level road. The same motorcar can be pushed by three persons to produce an acceleration of 0.2 m s^-2. With what force does each person push the motorcar? (Assume that all persons push the motorcar with the same muscular effort.)

Answer:

Mass of the motor car = 1200 kg

Only two persons are able to move the car with constant velocity. So, the acceleration acquired by the car is given by the third person. Thus the third person is responsible for the acceleration generated.

Acceleration, a = 0.2 m/s²

From Newton’s second law of motion:

Force = Mass × Acceleration

F = 1200 × 0.2 = 240 N

Hence, each person applies a force of 240 N to push the motor car.

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