Question

some times electric bulb does glow even when electric switch is (No) then we say that bulb is​

Answer 1

Answer:

fused

it happens when the tungeston wire breaksup or melts down .

HOPE IT HELPS......

Answer 2

in contrast to incandescent bulbs or halogen lamps an LED lamp has a high resistance due to the integrated power supply unit. The serial connection of the glow lamp closes the circuit even when the switch is turned off. As a consequence a low voltage drop appears to the LED driver so the LED still lights up weakly.