SECTION : Force on Charges      

A positive point charge sits at rest at the origin in a time-changing external field. This external field is uniform in space but varies in time as indicated by the orange vector in the animation. The animation shows the dramatic inflow of energy into the neighborhood of the charge as the magnitude of the external electric field grows, with a resulting build-up of stress that transmits a downward force to the positive charge. The downward force is indicated by the white vector.