A 50.0-kilogram firefighter is on a ladder 10.0 meters above the ground. When the firefighter descends to 5.00 meters above the ground, the potential energy stored in the gravitational field due to firefighter’s position will decrease by

Two steel balls, each of mass m, are welded to a light rod of length l and negligible mass and are initially at rest on a smooth horizontal surface. a horizontal force of magnitude f is suddenly applied to the rod as shown. determine (a) the instantaneous acceleration a of the mass center g and (b) the corresponding rate at which the angular velocity of the assembly about g is changing with time.