Question

a wire of length L has resistance R is bent into a circle then the resistance between the ends of diameter of circle is

Answer 1

If a wire of resistance R is bent in the form of a circle the effective resistance between the ends of a diameter is R/4.

Reason--

New resistance at 2 opposite sides will be R/2 and they will be in parallel

So,
R.eq=[(R/2)×(R/2)]/(R/2)+(R/2)]

R.eq=R/4

Answer 2

Resistance = R/4

reason

resistance of wire = R

Resistance of circle when divided ny diameter=

R/2

Now, refer to attachment.

so, 1/R = 1/R/2+1/R/2

1/R = 2/R+2/R

1/R = 4/R

R= R/4

Hope it helps

Regards, Akash Kumar

Thanks