When the resistance $R$ (indicated in the figure below) is changed from $1 \,k \Omega$. to $10 \,k \Omega$, the current flowing through the resistance $R'$ does not change. What is the value of the resistor $R'?$
  • A$5 k \,\Omega$
  • B$100 \,\Omega$
  • C$10 \,k \Omega$
  • D$1 \,k \Omega$
KVPY 2021, 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
    The $V-i$ graph for a conductor at temperature ${T_1}$ and ${T_2}$ are as shown in the figure. $({T_2} - {T_1})$ is proportional to
    View Solution
  • 2
    $A$ uniform copper wire carries a current $i$ amperes and has $p$ carriers per meter$^3$. The length of the wire is $\lambda$ meters and its cross-section area is $s$ meter $^2$. If the charge on a carrier is $q$ coulombs, the drift velocity in $ms^{-1}$ is given by
    View Solution
  • 3
    The potential difference across the $100\,\Omega$ resistance in the following circuit is measured by a voltmeter of $900 \,\Omega$ resistance. The percentage error made in reading the potential difference is
    View Solution
  • 4
    $A$ Wheatstone's bridge is balanced with a resistance of $625\, \Omega$ in the third arm, where $P, Q$ and $S$ are in the $1^{st}, 2^{nd}$ and $4^{th}$ arm respectively. If $P$ and $Q$ are interchanged, the resistance in the third arm has to be increased by $51\,\Omega$ to secure balance. The unknown resistance in the fourth arm is ............. $\Omega$
    View Solution
  • 5
    A solenoid is at potential difference $60\, V$ and current flows through it is $15$ ampere, then the resistance of coil will be ............ $\Omega$
    View Solution
  • 6
    A cell of negligible resistance and $e.m.f.$ $2$ $volts$ is connected to series combination of $2$, $3$ and $5\, ohm$. The potential difference in volts between the terminals of $3\, ohm$ resistance will be
    View Solution
  • 7
    In the circuit shown $E, F, G$ and $H$ are cells of $\mathrm{e.m.f.}$ $2\,V, 1\,V, 3\,V$ and $1\,V$ respectively and their internal resistances are $2\,\Omega , 1\,\Omega , 3\,\Omega$ and $1\,\Omega$ respectively.
    View Solution
  • 8
    When two identical batteries of internal resistance $1 \Omega$ each are connected in series across a resistor $\mathrm{R}$, the rate of heat produced in $R$ is $J_1$. When the same batteries are connected in parallel across $R$, the rate is $\mathrm{J}_2$. If $\mathrm{J}_1=2.25 \mathrm{~J}_2$ then the value of $\mathrm{R}$ in $\Omega$ is
    View Solution
  • 9
    As shown in the schematic below, a rod of uniform cross-sectional area $A$ and length $l$ is carrying a constant current $i$ through it and voltage across the rod is measured using an ideal voltmeter. The rod is stretched by the application of a force $F$. Which of the following graphs would show the variation in the voltage across the rod as function of the strain $\varepsilon$ when the strain is small. Neglect Joule heating.
    View Solution
  • 10
    Voltmeters $V_1$ and $V_2$ are connected in series across a $D.C.$ line. $V_1$ reads $80\, volts$ and has a per volt resistance of $200 \,\Omega$. $V_2$ has a total resistance of $32 \,kilo-ohms$. The line voltage is ............. 
    View Solution