Work done against frictional force equals the kineticenergy of the body. when a body of mass m, moves with velocity v, it has kinetic energy k=
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mv2 this energy is utilized in doing work against the frictional force between the tyres of the car and road. ∴ kinetic energy = work done against friction force
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m2=µ mgs where s is the distance in which the car is stopped and µ is coefficient kinetic friction . Given v=v0 s=