Question

What happens to the glow of the other two bulbs when the bulb $B_1$ gets fused?

• A. The glow of the bulbs $B_2$ and $B_3$ will remain the same.
• B. $B_2$ will more glow than $B_3$
• C. $B_2$ will less glow than $B_3$
• D. $B_1$ is more glow than $B_2$ and $B_3$.

Answer 1

The correct option is A The glow of the bulbs $B_2$ and $B_3$ will remain the same.

A bulb is just a high resistance wire which converts electricity into light energy, the more the current, intenser the brightness. Initially, the current across the circuit is 3A and the voltage is 4.5V. Hence, the resistance will be $R=V/I=4.5/3=1.5ohms.$

Now, when one bulb B1 fuses of, that resistance is removed and current flows only to bulbs B2 and B3. As it is a parallel circuit, the voltage and current flows equally in every stream of the circuit.

Hence, the resistance will remain the same as 1.5 ohms and the bulbs will continue to glow and remain the same.