A football player pushes a 670-N blocking sled. The coefficient of static
friction
between sled and grass is 0.73, and the coefficient of kinetic friction
between sled and grass is 0.68.
a. How much force must the player exert to start the sled in motion?
b. How much force is required to keep the sled in motion?
c. Answer the same two questions with a 100-kg coach standing on the back
of the sled.