Q.
A body of mass 40kg resting on rough horizontal surface is subjected to a force P which is just enough to start the motion of the body. If μs=5,μx=0.4,g=10m/s2 and the force P is continuously applied on the body, then the acceleration of the body is
Force P=fm=μ0mg( when body is rest )
When the body starts moving with acceleration a then P−Fk=ma μ0mg−μkmg=ma a=(μ0−μk)g =(0.5−0.4)10 =0.1×10m/s2=1m/s2