CBSE Class 8 Answered

The bulb may not glow because of the following reasons:

(i) Liquid in the beaker may be non-conducting. In such a case, the electric current would not be able to pass through the liquid. Hence, the circuit will not be complete.

(ii) The conductivity of the liquid may be very low and so the current flowing through the circuit may be too weak to produce enough heat in the filament of the bulb so as to make it glow.

(iii) The battery may be exhausted and does not have sufficient energy to generate electricity.

(iv) The bulb may be fuse or the circuit connections may be loose.