Question

observe the following figure which bulb get fuse?

Answer 1

bulb A gets the fuse because the battery has only enough current for 1 bulb, but if you add another cell it will light bulb B also.

Answer 2

Hey dear,

● Answer -
Bulb A

● Explaination -
# Given -
Pa = 50 W
Va = 220 V
Pb = 100 W
Vb = 220 V
V = 440 V

# Solution -
Current through bulb A -
Ia = Pa / Va
Ia = 50 / 220
Ia = 0.227 A

Current through bulb B -
Ib = Pb / Vb
Ib = 100 / 220
Ib = 0.455 A


Resistance of bulb A -
Ra = 220^2 / 50
Ra = 968 ohm

Resistance of bulb B -
Rb = 220^2 / 100
Rb = 484 ohm

Total resistance in series -
R = Ra + Rb
R = 968 + 484
R = 1452 ohm

Current flowing through circuit is -
I = V / R
I = 440 / 1452
I = 0.303 A


As I > Ia, bulb A will get lit .


Hope this helps you...