An iceboat of mass M = 250 kg sits motionless on a frozen lake. The boat is tied to a stake by a rope of length R = 100 m. A steady wind starts to blow from the West, pushing the boat with a constant force F = 150 N. The boat slides along the ice, moving in a circular arc as the rope stretches taut. The coefficient of kinetic friction between the boat's runners and the ice is mu_k = 0.03.

How fast is the boat moving when it reaches the point marked "X"?

You can do this problem by breaking it up into two pieces:

  1. calculate the work done on the boat by the wind (just as in the previous problem)
  2. calculate the work done on the boat by friction
Then add the two pieces together to find the total work done on the boat as it swings downwind.