Shows the shape of an electric field.

Two foil plate systems (One showing two point charges, the other a parallel plate capacitor), Grass seed, 9 KV power supply

Metal foil fixed on insulating clear plates are placed on the overhead projector on four insulating blocks and grass seed is sprinkled over the area. An AC supply of 9 KV is connected to the plates and the seeds align in the direction of the field.

This demo can also been run using the Wimhurst Generator This demo is also most effective when one person sprinkles the seeds over the plate as the power source is running, as to prevent clumping of the grass seeds. Updated on 06/10/13