KCET 2014 Physics Solved Paper

Given, for potentiometer experiment for cell of emf E1=1.25 , balancing length L1=30 cm.
For cell of emf E2 , balancing length L2=40cm .
We know E ∝ L
⇒‌

E1

E2

=‌

L1

L2

⇒‌

1.25

E2

=‌

30

40

⇒E2=1.25×‌

4

3

=1.666V
Therefore E2~1.67V
Emf of second cell is 1.67