Figure shows a part of an electric circuit. The potentials at points $a , b$ and $c$ are $30\,V , 12\,V$ and $2\,V$ respectively. The current through the $20 \Omega$ resistor will be $........\,A$
  • A$0.4$
  • B$0.2$
  • C$0.6$
  • D$1.0$
JEE MAIN 2023, 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
    A current of $2\,A$ flows through a wire of crosssectional area $25.0\,mm ^2$. The number of free electrons in a cubic meter are $2.0 \times 10^{28}$. The drift velocity of the electrons is $...............\times 10^{-6}\,ms ^{-1}$ (given, charge on electron $=1.6 \times 10^{-19}\,C$ )
    View Solution
  • 2
    A potential $V_0$ is applied across a uniform wire of resistance $R$. The power dissipation is $P_1$. The wire is then cut into two equal halves and a potential of $V _0$ is applied across the length of each half. The total power dissipation across two wires is $P_2$. The ratio $P_2: P_1$ is $\sqrt{x}: 1$. The value of $x$ is $.............$.
    View Solution
  • 3
    What is the number density of donor atoms which must be added to a pure germanium semiconductor to make $n-$ type semiconductor of conductivity $6.4\ {\Omega ^{ - 1}}\,c{m^{ - 1}}$?  The mobility of electr ons in $n-$ type germanium is $4 \times {10^3}\ cm^2\ V^{-1}\ s^{-1}$. Neglect the contribution of holes to conductivity
    View Solution
  • 4
    In the Wheatstone's bridge shown, $P = 2\,\Omega ,$ $Q = 3\,\Omega ,$ $R = 6\,\Omega $ and $S = 8\,\Omega $. In order to obtain balance, shunt resistance across '$S$' must be .............. $\Omega$
    View Solution
  • 5
    To draw maximum current from a combination of cells, how should the cells be grouped
    View Solution
  • 6
    Wheatstone bridge principle is used to measure the specific resistance $\left(S_1\right)$ of given wire, having length $L$, radius $r$. If $X$ is the resistance of wire, then specific resistance is: $S_1=X\left(\frac{\pi r^2}{L}\right)$. If the length of the wire gets doubled then the value of specific resistance will be :
    View Solution
  • 7
    A rectangular parallelopiped is measured as $1\,cm \times 1\,cm \times 100\,cm$. If its specific resistance is $3 \times 10^{-7}\,\Omega\,m$, then the resistance between its two opposite rectangular faces will be $..........x^{-7} \Omega$.
    View Solution
  • 8
    Two square metal plates $A$ and $B$ are of the same thickness and material. The side of $B$ is twice that of $A$. These are connected as shown in series. If the resistances of $A$ and $B$ are denoted by $R_A$ and $R_B,$ then $(R_A/R_B)$ is
    View Solution
  • 9
    Under what condition current passing through the resistance $R$ can be increased by short circuiting the battery of emf $E_2$. The internal resistances of the two batteries are $r_1$ and $r_2$ respectively.
    View Solution
  • 10
    In the circuit here, the steady state voltage across capacitor $C$ is a fraction of the battery $e.m.f.$ The fraction is decided by
    View Solution