Hertz’s photoelectric effect
Stories from Physics
for 11-14
14-16
16-19
Heinrich Hertz made perhaps the earliest recorded observation of the photoelectric effect in 1887, during his experiments on radio waves. Hertz had set up a receiver for radio waves consisting of a spark gap in a curved piece of brass capped with small metal spheres. Current induced by radio waves in the u-shaped conductor would produce a spark between the spheres. Hertz observed that when he placed a piece of glass in front of the loop, the size of the spark decreased. And when he replaced the glass with a quartz plate, which allows ultraviolet light to pass through, the spark returned to its original size. Hertz was mystified by the results commenting:
…the effect is striking and yet totally puzzling. Naturally it would be nicer if it were less puzzling; however, there is some hope that, when this puzzle is solved, more new facts will be clarified than if it were easy to solve.
References
Hertz’s photoelectric effect
J. Pollard, Boffinology. The Real Stories Behind Our Greatest Scientific Discoveries, London, John Murray, 2010, pp. 43-45
J. E. Mulligan, Heinrich Rudolf Hertz (1857-1894). A Collection of Articles and Addresses. New York, Taylor and Francis, 2019, p. 38.
