- Homework Statement
- A block of mass m slides along the track with kinetic friction μ. A man pulls the block through a rope which makes an angle theta with the horizontal. The block moves with a constant speed v. Power delivered by the man is?
- Homework Equations
P= force in the direction of velocity x velocity
Frictional force = coefficient of friction x normal reaction
Force along the horizontal would be
Frictional force (which is in the opposite direction )= μmg
So net force in the direction of velocity = Tcos(theta)-μmg
But this is not so, the right answer is given to be Tvcos(theta). Why should we not consider the frictional force acting here ?