Is work done by a non conservative force always negative ? Comment.

Is the work done by non conservative force is always negative ? Discuss .

Can work done by a non - conservative force be positive ?

Statement I: if work done by conservative force is negative then potential energy associated with that force should increase. Statement II: This is from the reaction Delta u =- W. Here Delta u is change in potential energy and W is work done by conservative force.

The work done by the conservative force in a cycle is

(I) The work done by a non - conservative force, around the closed path is zero. (II) The co - efficient of restitution is e. Which statement is incorrect ?

When is work done by a force negative ?

The work done by the conservative force for a closed path is