A 70 kg mass is on the edge of a cliff and falls 40 meters before striking a surface where it stops. What is its potential energy? How much kinetic energy does the mass have just before it strikes the surface? What is the velocity of the mass just before it strikes the surface? How much momentum does the mass have just before it strikes the surface?

Asailboat is traveling to the right when a gust of wind causes the boat to accelerate leftward at 2.5m/s2 for 4s. after the wind stops, the sailboat is traveling to the left with a velocity of 3.0m/s.assuming the acceleration from the wind is constant, what was the initial velocity of the sailboat before the gust of wind? answer using a coordinate system where rightward is positive.