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)
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Solution
Given, mass of the car (m) = 1200kg
When the third person starts pushing the car, the acceleration (a) is 0.2 ms-2. Therefore, the force applied by the third person (F = ma) is given by:
F = 1200kg × 0.2 ms-2 = 240N
The force applied by the third person on the car is 240 N. Since all 3 people push with the same muscular effort, the force applied by each person on the car is 240 N.
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