Answer to Question #21376 in Mechanics | Relativity for M Waqas

Question

Give a situation in which positive work is done by a static frictional force?

Answer 1

The direction of the frictional force on theportion of the wheel contacting the ground is opposite to the direction of the
velocity of this portion of the wheel with respect to the
ground. Neglecting drag, the force of static friction is the only external
force acting on the car in the horizontal direction, and without it there would
be no net force to accelerate the car. It 's mean what frictional force
done positive work.