Question

a wire of resistance 8 ohm is bent in the form of circle what is effective resistance between the ends of a diameter AB

Answer 1

Thank you for asking this question, the options for this question are missing:

Here are the missing options:

A) Rα4π2(2π−α)

B) R2π(2π−α)

C) R(2p  a)

D)  4πRα(2π−α)

Answer:

The correct answer for this question is Option A: Rα4π2(2π−α)

RXWY=R/2πr×(rα)=Rα/2π  

(∵α=l/r)

and  

RXZY=R/2πr×r(2π−α)

=R/2π(2π−α) Req

=RXWYRXZY/RXWY+RXZY

=Rα/2π×R/2π(2π−α)/Rα/2π+R(2π−α)/2π

=Rα/4π2(2π−α)

If there is any confusion please leave a comment below.