Q 12-03-158JEE MainJEE Main 2022 (24 Jun, Shift 1)Easy
In a potentiometer arrangement, a cell gives a balancing point at $75\ \text{cm}$ length of wire. This cell is now replaced by another cell of unknown emf. If the ratio of the emfs of the two cells respectively is $3 : 2$, the difference in the balancing length of the potentiometer wire in the above two cases will be ______ cm.
Numerical value type. Enter your answer.
Answer: 25
$E\propto l$: $\dfrac{E_1}{E_2} = \dfrac{75}{l_2} = \dfrac32\Rightarrow l_2 = 50\ \text{cm}$.
Difference $= 75 - 50 = 25\ \text{cm}$.
Solution by Sreeraj P, M.Sc Physics