Science
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 ms-2. With what force does each person push the motorcar? (Assume that all persons push the motorcar with the same muscular effort)
Laws of Motion
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Answer
Given,
Mass of the car (m) = 1200 kg
When two persons push the car, it moves with uniform velocity i.e., acceleration of the car is 0 and total force on the car is balanced.
Hence, the force that accelerates the car is given by the third person.
Acceleration when third person starts pushing the car (a) = 0.2 ms-2
We know, Force = mass x acceleration
Substituting we get,
F = 1200 × 0.2 = 240 N
The force applied by third person = 240 N.
As all 3 people push with the same muscular effort, hence, force applied by each person = 240 N
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