How does an electrical field change when it interacts with an opposing field

Do you agree with scientist’s prediction about the warming of alaska and other polar regions?

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.

This is the number of complete movements of a wave per second.