In the figure,the potentiometer wire AB of le | vedclass

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

Question

(B) The current $I$ flowing through the potentiometer wire $AB$ is given by the total $emf$ divided by the total resistance in the primary circuit:$I

Vedclass · Accepted Answer

$\frac{5L}{9}$

Vedclass · Answer

(B) The current $I$ flowing through the potentiometer wire $AB$ is given by the total $emf$ divided by the total resistance in the primary circuit:$I = \frac{\varepsilon}{r + 9r} = \frac{\varepsilon}{10r}$The potential difference $V_{AB}$ across the potentiometer wire $AB$ is:$V_{AB} = I 	imes 9r = \left( \frac{\varepsilon}{10r} ight) 	imes 9r = \frac{9\varepsilon}{10}$The potential gradient $K$ along the wire $AB$ is the potential drop per unit length:$K = \frac{V_{AB}}{L} = \frac{9\varepsilon}{10L}$For the galvanometer $G$ to show no deflection,the potential difference across the length $AJ$ must be equal to the $emf$ of cell $C$ $(\varepsilon / 2)$:$V_{AJ} = K 	imes AJ = \frac{\varepsilon}{2}$Substituting the value of $K$:$\left( \frac{9\varepsilon}{10L} ight) 	imes AJ = \frac{\varepsilon}{2}$Solving for $AJ$:$AJ = \frac{\varepsilon}{2} 	imes \frac{10L}{9\varepsilon} = \frac{5L}{9}$

Similar Questions

The cathode of a photoelectric cell is changed such that the work function changes from $W_1$ to $W_2$ $(W_2 > W_1)$. If the current before and after change are $I_1$ and $I_2$,all other conditions remaining unchanged,then (assuming $hv > W_2$):

The smallest unit of life is...

At a given temperature,the pressure of an ideal gas of density $\rho$ is proportional to

$A$ proton, a deuteron, and an $\alpha$-particle having the same momentum enter a region of uniform electric field between the parallel plates of a capacitor. The electric field is perpendicular to the initial path of the particles. The ratio of deflections suffered by them is

The resistance in the following circuit is increased at a particular instant. At this instant,the value of resistance is $10 \, \Omega$. The current in the circuit will be now:

Vedclass Test Series

Exam Paper Generator

Online Exam Module