Answer to Question #263880 in Atomic and Nuclear Physics for long

Question

As a sled moves across a flat snow-covered field at constant velocity, is any work done?

How does air resistance enter into the picture?

Answer 1

Since there is no change in speed, there is no change in kinetic energy, hence no net work done. Whatever force is propelling the sled is doing work, and air resistance and other frictional forces are doing negative work, but the net work is zero.