As a wave travels through a medium, it displaces the particle perpendicular to the motion of the wave. We can conclude that this is a

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Often called simply "velocity," this is the velocity of an object at a particular moment in time.

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.