In the figure, the potentiometer wire $AB$ of length $L$ and resistance $9r$ is joined to the cell $D$ of $\mathrm{emf}$ $\varepsilon$ and internal resistance $r$. The cell $C’s$ $\mathrm{emf}$ is $\varepsilon /2$ and its internal resistance is $2r$. The galvanometer $G$ will show no deflection when the length $AJ$ is
  • A$\frac{{4L}}{9}$
  • B$\frac{{5L}}{9}$
  • C$\frac{{7L}}{{18}}$
  • D$\frac{{11L}}{{18}}$
Diffcult
art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    Four resistances of $15\; \Omega, 12\; \Omega, 4 \;\Omega$ and $10\; \Omega$ respectively in cyclic order to form Wheats tone's network. The resistance that is to be connected in parallel with the resistance of $10\; \Omega$ to balance the network is .................. $\Omega$
    View Solution
  • 2
    Three resistances, each of $1\, ohm$, are joined in parallel. Three such combinations are put in series, then the resultant resistance will be ............. $ohm$
    View Solution
  • 3
    In the circuit shown, the reading of ammeter when switch $S$ is open and when switch $S$ is closed respectively are
    View Solution
  • 4
    Two identical bulbs are connected in parallel across an ideal source of emf $E$. The ammeter $A$ and voltmeter $V$ are ideal. If bulb $B_2$ gets fused, then
    View Solution
  • 5
    $V-i$ graphs for parallel and series combination of two identical resistors are as shown in figure. Which graph represents parallel combination
    View Solution
  • 6
    To measure the temperature coefficient of resistivity $\alpha$ of a semiconductor, an electrical arrangement shown in the figure is prepared. The arm BC is made up of the semiconductor. The experiment is being conducted at $25^{\circ} \mathrm{C}$ and resistance of the semiconductor arm is $3 \mathrm{~m} \Omega$. Arm BC is cooled at a constant rate of $2^{\circ} \mathrm{C} / \mathrm{s}$. If the galvanometer $\mathrm{G}$ shows no deflection after $10 \mathrm{~s}$, then $\alpha$ is :
    View Solution
  • 7
    In the following circuit, $18\,\Omega $ resistor develops $2\,J/sec$ due to current flowing through it. The power developed across $10\,\Omega $ resistance is .............. $W$
    View Solution
  • 8
    A uniform wire of length $l$ and radius $r$ has a resistance of $100\, \Omega $. It is recast into a wire of radius $\frac{r}{2}$. The resistance of new wire will be ............... $\Omega$
    View Solution
  • 9
    A current of $2\,A$ flows through a $2\,\Omega$ resistor when connected across a battery. The same battery supplies a current of $0.5\,\, A$ when connected across a $9 \,\,\Omega$ resistor. The internal resistance of the battery is 
    View Solution
  • 10
    In the figure shown, if the internal resistance of the battery is $1\, ohm$, the reading of the ammeter will be ............... $A$
    View Solution