The figure shows a block in the influence of a force 500N. Friction working is 100N. The net force causes a displacement of 3m of the body.Find the work done against friction.
11Net Force=APPLIED FORCE-FRICTIONAL FORCE
=500N-100N
400N
Displacement 3m is due to the net force 400n.
The applied force is greater than frictional force.So the direction of net force is against frictional direction.
Work done=Net Force*Displacement
=4ooN*3m
=1200J
62The work done should be -300J
Is there more than it meets the eyes?
Arnab is it ur doubt!
21Sir, I know its easy. But during the exam i thoght work done against friction means work done by the force acting opposite to friction.
But now i come to know that it should be the work done by the friction only.
1For the friction, displacement is in the opposite direction. So, F*d=100*3=-300J. Am i right sir?
