Download the app

Questions  

Two filament bulbs A and B are connected in series combination. Filament of A is made of carbon and that of B is made of platinum. At t=0, the combination is connected to a d.c. source. Then after a long time 

a
brightness of A will be more than the brightness of B
b
brightness of A will be less than the brightness of B
c
brightness of A will be same as that  of B
d
Nothing can be said about the brightness of A as information  given is not sufficient.

detailed solution

Correct option is B

The same current flowing through the filaments of A and B with the rise of temperature, resistivity of carbon decreases and that of platinum increases since rate of heat generation is i2R,and brightness is proportional to rate of heat generation. Energy loss or heat is more where resistance is more.

Talk to our academic expert!

+91

Are you a Sri Chaitanya student?


Similar Questions

In a common-base mode of transistor, the collector current is 5 488 mA for an emitter current of 5 .60 mA. The value of the base current amplification factor (p) will be


phone icon
whats app icon