N identical cells whether joined together in series or in parallel, give the same current, when connected to an external resistance of 'R'. The internal resistance of each cell is:-

Answer

`9 cm` from centre of bigger circle (leftwards)

Explanation

`x_(cm) = ((rho(pi xx 56^(2))/(4)) xx 28 + (rho(pi xx 42^(2))/(4)) xx 35)/((rho(pi xx 56^(2))/(4)) - (rho(pi xx 42^(2))/(4)))`
`= 9 cm` from left edge