An electric bulb is connected to a cell through a switch as shown in Fig. 12.7. When the switch is brought in ‘ON’ position, the bulb does not glow. What could be the possible reasons for it? Mention any two of them.

The two possible reason behind that are:

● The first possible reason is that may be the filament inside the bulb is broken. Filament is the main component of the bulb which glows when the current passes through it. It glows because when electricity passes through the filament it got heat up. Heating causes the glowing of bulb. But the extensive heating can break the filament and will result in not glowing of the bulb.


● The second possible reason is that the electric cell is completely used up or all the chemicals have been used already and there is no electricity left in it. As cell is the only source of the power of the circuit, if it is completely used the circuit will not work and the bulb will not glow.


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