Question

A hemispherical network of radius a is made by using a conducting wire of resistance per unit length 'r'. The equivalent resistance across OP is.

• A. $\frac{8ar}{(2+\pi )}$
• B. $\frac{8ar}{(2-\pi )}$
• C. $\frac{(2+\pi )ar}{8}$
• D. $\frac{(2-\pi )ar}{8}$

Answer 1

The correct option is C $\frac{(2+\pi )ar}{8}$

$Rop=(ar+\frac{\pi }{2}ar)||(......)||(.....)||(......)$

$\frac{1}{4}ar(\frac{\pi }{2}+1)$

$\Rightarrow \left(\frac{\pi +2}{8}\right)ar$