Out of two electric bulbs of 50 W - 220 V and 100W - 220 V. Which one will glow brighter when they are connected (i) in series, and (ii) in parallel?

Explanation

The resistance of the bulb is defined as `R= (V^(2))/(P)` So the resistance of 50 W bulb is double than P the resistance of 100 W bulb. When they are connected in series the current through both bulbs is same. Hence 50 watt bulb will be brighter because `P= I^(2)R`. In parallel, the voltage will be same in both bulbs. So, the 100 watt bulb will be brighter because `P= (V^(2))/(R)`