| Hertz effect [`hǝrts i´fekt] ELECTROMAGNETISM A dependence of the attenuation of a linearly polarized electromagnetic wave passing through a grating of metal rods on the angle between the electric vector and the rod direction, with the attenuation being a minimum when the two are perpendicular. ELECTRONICS Increase in the length of a spark induced across a spark gap when the gap is irradiated with ultraviolet light. |