Light Effects
المؤلف:
GEORGE A. HOADLEY
المصدر:
ESSENTIALS OF PHYSICS
الجزء والصفحة:
p-339
2025-11-30
20
The light effects of the discharge can best be studied at night, though a room that can be made nearly dark with curtains will do. In the first place, the machine itself affords excellent illustrations of these effects. The shower of purple sparks that follow one another so rapidly that the images of six or eight are continually seen, - the sharp spark of the condenser discharge, which makes everything dazzlingly bright, and which takes place so quickly that the rapidly rotating wheel, as seen by its light, seems to stand still, - the cascade of minute sparks that flows over the plate near the collecting combs, - and the glow of light that tips every point of the combs, - all are light effects of the most interesting kind.
Demonstration. - Cover one side of a dry white pine board with a heavy coat of shellac. Next place on this a layer of thin tin foil and cover this with shellac, rubbing it down fast to the board. Dry thoroughly and then with a sharp knife cut the tin foil into squares a quarter of an inch on a side. Connect the tin foil at the ends of the board with the terminals of the machine, and the discharge will be seen to pass the entire length of the tin foil, causing a spark at every place where the conductor has been cut.
Such boards can be made in any desired shape; they illustrate the fact that if a discharge takes place along a broken conductor a spark will occur at every gap.
Demonstration. -Get a piece of No. 30 magnet wire and with a knife or pair of cutting pliers cut the wire every half inch without cutting the insulation. Suspend this from the ends over the terminals of the machine, and when the machine is put in motion every break in the wire will furnish a bright spark. The insulation will hold the pieces of wire in place, and they can be made into many fanciful shapes.
الاكثر قراءة في الكهربائية
اخر الاخبار
اخبار العتبة العباسية المقدسة
