Question

Some electric bulbs are connected in series across a $220\,V$ supply in a room. If one bulb is fused, then remaining bulbs are connected again in series across the same supply. The illumination in the room will be

• A. increase
• B. decrease
• C. remain the same
• D. not continuous

Answer 1

Answer: (A)

increase

Answer 2

From Joule's law, the heat produced is given by $P=\frac{V^{2}}{R}$ where $V$ is potential and $R$ the resistance. When one bulb is fused, the total resistance of the circuit decreases.
Hence, $(P)$ illumination increases.