EM.9(1) – Electric Light Dimmer – RL in Series
A light bulb (a flood light) is connected in series with an inductor and an AC power source. The inductor consists of a large coil with a long sliding iron core. The light bulb is bright when the iron core is out of the coil. The light gets dimmer as the core is pushed inside the coil.
EM.9(2) – LRC in Series
A flood light R, a capacitance C and an inductance L are connected in series to an AC power source. In this circuit, the current depends not only on R but also on the reactance X = XL – XC. The inductance L has a long sliding iron core which allows one to vary L. When XL is equal to XC, the circuit draws the maximum current, giving the brightest light to the bulb.
