Question

What happens when the supply voltage to a light bulb is increased ?
1) The bulb glows brighter
2) The bulb consumes less power
3) The bulb consumes more power
4) The power consumption does not change.
Which of the above statements are true?

• A. 1, 2 and 3
• B. 1 and 4
• C. 1 and 3
• D. 2 and 3

Answer 1

Answer: (C)

1 and 3

$P=I\times V$

$=\frac{V^2}{R}$ $\because I=V/R$
So, when voltage increased $⟶$ power consumption will be more thereby glowing the bulb brighter.