To compare EMF of two cells using potentiometer the balancing lengths obtained are 200 cm and 150 cm. The least count of scale is 1 cm. The percent

STUDY MATERIALS
COURSES
MORE
SUCCESS STORY
ADMISSION
STORE

Back

JEE ADVANCE

CLASS XI - XII
CRASH COURSE

CLASS XI - XII

CRASH COURSE

JEE MAIN

CLASS XI - XII
CRASH COURSE

CLASS XI - XII

CRASH COURSE

NEET

CLASS XI - XII
CRASH COURSE

CLASS XI - XII

CRASH COURSE

BITSAT

CLASS XI - XII

CLASS XI - XII

CBSE BOARD

CLASS IX

CLASS X

CLASS XI

CLASS XII

CLASS VI

CLASS VII

CLASS VIII

UP BOARD

CLASS IX
CLASS X
CLASS XI
CLASS XII

CLASS IX

CLASS X

CLASS XI

CLASS XII

CUET

CRASH COURSE

CRASH COURSE

Courses

CLASSROOM COURSES
ONLINE COURSES

ONLINE COURSES

More

Solution

Q.
To compare EMF of two cells using potentiometer the balancing lengths obtained are 200 cm and 150 cm. The least count of scale is 1 cm. The percentage error in the ratio of EMFs is ______. [2026]

1 1.55

2 1.45

3 1.65

4 None of these

Ans.
(4)

$ε = λ ℓ$

$Potential gradient$

$ε_{1} = λ ℓ_{1}$

$ε_{2} = λ ℓ_{2}$

$y = \frac{ε_{1}}{ε_{2}} = \frac{ℓ_{1}}{ℓ_{2}}$

$\frac{Δ y}{y} = \frac{Δ ℓ_{1}}{ℓ_{1}} + \frac{Δ ℓ_{2}}{ℓ_{2}}$

$\frac{Δ y}{y} = \frac{1}{200} + \frac{1}{150}$

$\frac{Δ y}{y} \times 100 = (\frac{1}{200} + \frac{1}{150}) \times 100$

$= (\frac{3 + 4}{600}) \times 100 = \frac{7}{6} = 1.16 %$

Want Us to Email you About Special Offers & Updates?