Correct Answer - c
Let `epsilon_(1)` and `epsilon_(2)` be the emits of two cells and `K` be the potential gradient of potentiometer wire
case (i), `epsilon_(1) + epsilon_(2) = K xx 50`….(i)
case (ii), `epsilon_(1) - epsilon_(2) = K xx 10`….(ii)
Dividing (i) and (ii), we get
`(epsilon_(1) + epsilon_(2))/(epsilon_(1) - epsilon_(2)) = (50)/(10) = 5`
or `epsilon_(1) + epsilon_(2)= 5epsilon_(1) - 5 or epsilon_(2) or 4epsilon_(1) = 6 or epsilon_(2)`
or `(epsilon_(1))/(epsilon_(2)) = (6)/(4) = (3)/(2)`