Question

You are participating in the Iditarod, and your sled dogs are pulling you across a frozen lake with a force of 1200N while a 300N wind is blowing at you at 135 degree from your direction of travel. What is the net force, and will your kinetic energy increase or decrease?

Answer 1

Fn = 1200 + 300[135o] = 1200 + 300*Cos135+i300*sin135 = 989 + 212i = 1011N.
KE decreased.