Atruck covers 40.0 m in 7.10 s while smoothly slowing down to a final velocity of 2.75 m/s.. (a) find the truck's original speed.

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.