Point charge dynamics near a grounded conducting plane

摘要

The classic image problem in electromagnetism involves a grounded infinite conducting plane and a point charge. The force of attraction between the point charge and the plane is identified using an equivalent-field picture of an image charge with an opposite sign equidistant behind the plane, resulting in a 1/r~2 attractive force between the original charge and the plane. If the point charge is released from rest, it will reach the plane in a time τ, which has not been calculated correctly. The inconsistency is clarified along with an improved solution to the classic image problem. Similar electromagnetism problems are also discussed.