A group of N cells whose e.m.f. varies directly with the internal resistance as per the equation `E_(n)=1.5r_(n)` are connected as shown in the figure above. The current I in the circuit is

Options

A. 5.1 amp
B. 0.51 amp
C. 1.5 amp
D. 0.15 amp

Answer

C

Explanation

`sumE_(n)=1.5rxx(n(n+1))/(2)`
`sumr_(n)=rxx(n(n+1))/(2),I=(sumE_(n))/(sumr_(n))=1.5` amp.