In a potentiometer arrangement, a cell of emf 1.20 V gives a balance point at 36 cm length of wire. This cell is now replaced by another cell of emf 1.80 V. The difference in balancing length of potentiometer wire in above conditions will be ___________ cm.
Answer (integer)
18
Solution
<p>$E \propto I$</p>
<p>${{1.2} \over {1.8}} = {{36} \over {I'}}$</p>
<p>$I' = {3 \over 2} \times 36 = 54$ cm</p>
<p>$\Delta I = I' - I = 54 - 36 = 18$ cm</p>
About this question
Subject: Physics · Chapter: Current Electricity · Topic: EMF and Internal Resistance
This question is part of PrepWiser's free JEE Main question bank. 120 more solved questions on Current Electricity are available — start with the harder ones if your accuracy is >70%.