JEE Main2012PhysicsCurrent ElectricityActual
Two electric bulbs marked 25 ~W -220 ~V and 100 ~W -220 ~V are connected in series to a 440 ~V supply. Which of the bulbs will fuse?
Options
- Aboth
- B100 ~W
- C25 ~W
- Dneither
Correct answer
C. 25 ~W
Step-by-step solution
Resistances of both the bulbs are R ₁= V ^2 P ₁ = 220^2 25 R ₂= V ^2 P ₂ = 220^2 100 Hence R₁>R₂ When connected in series, the voltages divide in them in the ratio of their resistances. The voltage of 440 ~V devides in such a way that voltage across 25 ~w bulb will be more than 220 ~V . Hence 25 ~w bulb will fuse.