Jack last edited by
A light bulb and an open coil inductor are connected to an ac source through a key. The switch is closed and after some time, an iron rod is inserted into the interior of the inductor. The glow of the light bulb(when iron rod is inserted )
c. Remains unchanged
tushar_goyal last edited by tushar_goyal
@jack As the iron rod is inserted, the magnetic field inside the coil magnetizes the iron hence increasing the magnetic field inside it.
Hence, the inductance of the coil increases.
As a result, a larger fraction of the applied ac voltage appears across the inductor, leaving less voltage across the bulb. This implies power decreases.
Therefore, the glow of the light bulb decreases.