The length of a potentiometer wire is L. A ce | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) Let the potential difference across the wire be $V$. The potential gradient $k$ is given by $k = \frac{V}{L_{total}}$.For the first case,the balan

Vedclass · Accepted Answer

$\frac{3 L}{10}$

Vedclass · Answer

(D) Let the potential difference across the wire be $V$. The potential gradient $k$ is given by $k = \frac{V}{L_{total}}$.For the first case,the balancing length $l_1 = \frac{L}{5}$. The e.m.f. $E$ is given by $E = k_1 l_1 = \frac{V}{L} \cdot \frac{L}{5} = \frac{V}{5}$.When the length of the wire is increased by $\frac{L}{2}$,the new total length becomes $L' = L + \frac{L}{2} = \frac{3L}{2}$.The new potential gradient is $k_2 = \frac{V}{L'} = \frac{V}{3L/2} = \frac{2V}{3L}$.Let the new balancing length be $l_2$. Then $E = k_2 l_2$.Equating the two expressions for $E$: $\frac{V}{5} = \frac{2V}{3L} \cdot l_2$.Solving for $l_2$: $l_2 = \frac{V}{5} \cdot \frac{3L}{2V} = \frac{3L}{10}$.

The length of a potentiometer wire is $L$. $A$ cell of e.m.f. $E$ is balanced at a length $\frac{L}{5}$ from the positive end of the wire. If the length of the wire is increased by $\frac{L}{2}$,at what distance will the same cell give a balance point?

Similar Questions

In a potentiometer experiment,the null point is obtained on the $7^{\text{th}}$ wire for a given cell. To shift the null point to the $9^{\text{th}}$ wire for the same cell,what should we do?

Sensitivity of a potentiometer can be increased by:

$A$ voltmeter reads the potential difference across the terminals of an old battery as $1.2 \, V$,while a potentiometer reads $1.4 \, V$. The internal resistance of the battery is $40 \, \Omega$. What is the resistance of the voltmeter in $\Omega$?

$A$ cell of $emf$ $2 \,V$ and internal resistance $5 \,\Omega$ is connected to a wire of length $100 \,cm$ and resistance $15 \,\Omega$. What is the potential gradient along the wire (in $,V/cm$)?

In the given potentiometer circuit,the length of the wire $AB$ is $3 \, m$ and its resistance is $R = 4.5 \, \Omega$. The length $AC$ for no deflection in the galvanometer is ............... $m$.

Vedclass Test Series

Exam Paper Generator

Online Exam Module