Question

three bulbs of rating 40 w, 60 w, and 100w, are desinged to work on 220 v mains . which bulb will glow most bright if they are connected in series across 220v mains

Answer 1

By applying the formula, P=VI
 P ∝ I
i.e, more is the power, the more is the current.

Since,the 100 W bulb has the maximum power,it will have the maximum current and thus the 100 W bulb will glow most brightly.