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

Two persons manage to push a motorcar of mass`1200kg` at a uniform vel

1.	Two persons manage to push a motorcar of mass`1200kg` at a uniform velocity along a level road. The same motorcar can be pushed by three persons to produce an acceleration of `0.2m//s^(2)`. With what force does each person push the motorcar? (Assume that all persons push the motorcar with the same muscular effort).
Answer» Here, mass of motorcar, `m= 1200kg` Let each person exert a push `F` on the motorcar. Total push of two person `= F+F=2F` As this push gives a uniform velocity to the motorcar along a level road, it must be a measure of the force of friction`(f)` between the motorcar and the road,i.e., `f=2F` As `spropt^(3)`, `v=(ds)/(dt)prop3t^(2)` Further, `a=(dv)/(dt)prop6t, i.e.,a propt`. When three person push, total force applied `=F+F+F=3F` Force that produces acceleration `(a=0.2m//s^(2))`, ie., `ma=3F-f=3F-2F=F` or `F=ma=1200xx0.2= 240N`