A cell, shunted by a8 $Ω$ resistance, is balanced across a potentiometer wire of length 3m. The balancing length is 2m when cell is shunted by 4 $Ω$ resistance. The value of internal resistance of the cell will be__________ $Ω$ .

4 Views|Posted 6 months ago

Asked by Shiksha User

1 Answer

Sort by:

Answered by

Vishal Baghel | Contributor-Level 10

6 months ago

R shunt Resistance

Given

CD = 3m

CF = 2m

Current through potentiometer wire

I = $\frac{v}{R_{0}} = \frac{V A}{ρ L}$ $\frac{}{_{}} \frac{}{}$ (1)

A Area of potentiometer wire

$ρ \to$ Resistivity of the wire

L Length of the potentiometer wire

Case 1 When 8 $Ω$ shunt is bal aced at 3m length

$V_{C D} = I R_{C D} = \frac{V}{ρ L} A * \frac{ρ C F}{A}$

$V_{C D} = \frac{V l}{L} = \frac{V * 3}{L}$

VCD = VAB = E – I1r

= $- \frac{E}{R + r} r = \frac{V}{L} * 3$ $\frac{}{} \frac{}{}$

$\Rightarrow E [1 - \frac{r}{8 + r}] = \frac{V}{L} * 3$ (2)

Case 2 When 4 $Ω$ shunt is balanced at 2m length

$V_{C F} = I R_{C F} = \frac{V}{ρ L} A * \frac{ρ C F}{A} = \frac{V * 2}{L}$

$V_{C F} = V_{A B} = E - I_{2} r$

Upvote

Taking an Exam? Selecting a College?

Get authentic answers from experts, students and alumni that you won't find anywhere else.

On Shiksha, get access to

66K

Colleges

1.2K

Exams

6.9L

Reviews

1.8M

Answers

Learn more about...

Physics NCERT Exemplar Solutions Class 11th Chapter Eight 2025

View Exam Details

Share Your College Life Experience

Didn't find the answer you were looking for?

Search from Shiksha's 1 lakh+ Topics

Ask Current Students, Alumni & our Experts

Quick Actions

Community GuidelinesUser Points System

QuestionsDiscussionsTags

Have a question related to your career & education?

See what others like you are asking & answering

A cell, shunted by a8 Ω resistance, is balanced across a potentiometer wire of length 3m. The balancing length is 2m when cell is shunted by 4 Ω resistance. The value of internal resistance of the cell will be__________ Ω .

Similar Questions for you