Question

A battery with no internal resistance is connected across identical light bulbs as shown in Fig. Q 26.7. When you close the switch S, will the brightness of bulbs ${\mathit{B}}_{\mathbf{1}}$ and${\mathit{B}}_{\mathbf{2}}$ change? If so, how will it change? Explain.

Short answer

Brightness will be the same for$B_1$ and $B_2$.

Step-by-step solution

Step 1: Definition of parallel connection

In a parallel circuit, all components are connected parallelly, connected all the first and last ends together in an electrical circuit. Voltage drop across all the components is same.

Determining the brightness of each bulb connected

The three bulbs are in parallel, therefore, the same voltage is across each bulb. And when is closed, no change in the voltage across$B_1$ and $B_2$. Therefore, the two bulbs will have the same brightness.

Thus, Brightness will be the same for$B_1$ and $B_2$.