Reference: EM34
Category: Electromagnetism
Purpose: Shows the direction of the electrostatic field.
Description: Perspex needles are mounted on pivots. Place this on a Perspex block on an overhead projector. Use the Whimshurst machine to build up charge. The Perspex needles point in the direction of the electric field. Electric field lines can also be shown by grass seeds in a shallow dish containing oil. (Grass seeds are in a box near to the Perspex needles.)
