A 25 W and a 100W bulb are joined in series to ac mains . Which bulb will grow brighter ? Explain
Solution
Since the bulbs are connected in series, the current through each bulb will be the same. Thus the power dissipated will be proportional to the resistance of each bulb. The bulb having more resistance will dissipate more power.
25W bulb has more resistance `(R=V2/P)` compared to 100 W bulb.
Thus 25W bulb having more power will glow brighter.
Hence, it will glow brighter
Since the bulbs are connected in series, the current through each bulb will be the same. Thus the power dissipated will be proportional to the resistance of each bulb. The bulb having more resistance will dissipate more power.
25W bulb has more resistance `(R=V2/P)` compared to 100 W bulb.
Thus 25W bulb having more power will glow brighter.
Hence, it will glow brighter