when we push the car,workdineyis 0,how

Workdone in physics = Force × ( part of displacement in same direction of force )

 

when we push the car, workdone against the gravitational force is zero because direction of gravitational force

and direction of displacement are mutually perpendicular .

 

Hence displacement in the direction of gravitational force is zero and workdone which is product of force

and displacement is zero.

 

When we push the car , our muscles applies the force nearly in horizontal direction parallel to earth surface.

Workdone by the force applied by muscles is not zero . This workdone equals product of force and displacement.