Electric Bulbs

Q. Three bulbs $B_1,B_2$ and $B_3$ are connected to the mains as shown in the figure. How will the brightness of bulb $B_1$ be affected if $B_2$ or $B_3$ are disconnected from the circuit?

1. Bulb $B_1$ becomes brighter
2. Bulb $B_1$ becomes dimmer
3. No change occurs in the brightness
4. Bulb $B_1$ becomes brighter if bulb $B_2$ is disconnected and dimmer if bulb $B_3$ is disconnected

Q. In the circuit shown in figure, if both the bulbs $B_1$ and $B_2$ are identical:

1. Only $B_2$ will glow because the capacitor has infinite impedance
2. Their brightness will be the same
3. $B_2$ will be brighter than $B_1$
4. As frequency of supply voltage is increased , the brightness of bulb $B_1$ will increase and that of $B_2$ will decrease.