List of top Physics Questions on Current electricity asked in UP Board XII

With the help of the given circuit, find out the total resistance of the circuit and the current flowing through the cell.
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On connecting a cell of e.m.f. 0.5 volt with an external resistance of 1.9 $\Omega$, the current flowing is 0.75 A. The internal resistance of the cell is:
Resistivity of a conducting wire depends on:
Define drift velocity and mobility of electrons in a metallic conductor. The length of a conducting rod is 1 m and the potential difference between its ends is 4 volt. Electron density in the conductor is \( 5 \times 10^{24}~\text{m}^{-3} \) and its resistivity is \( 50 \times 10^{-8}~\Omega\)-m. Calculate the drift velocity of the electrons in the metal.
Define electromotive force of a cell.
To measure potential difference from a galvanometer, we connect in it:
Electric field \( E \) is applied across a metallic wire of length \( l \) and area of cross-section \( A \). Obtain the formula of the relationship between the drift velocity (\( v_d \)) of free electrons of the conductor and electric field \( E \) in vector form.
How is a galvanometer converted into a voltmeter?
The correct relationship of mobility \( \mu \) of charge carrier with drift velocity \( v_d \) and electric field \( E \), is:
Two cells are of emf's \(E_1\) and \(E_2\) and their internal resistances are \(r_1\) and \(r_2\) respectively. They are joined in parallel to each other. Obtain the formula for the equivalent emf of this combination of cells.
What is the first law of Kirchhoff of the electrical circuit? Find out the potential difference between the ends of 2 \(\Omega\) resistor with the help of Kirchhoff's law. See the figure:
\includegraphics[width=0.5\linewidth]{image3.png}
A \( 4 \, \Omega \) resistance wire is bent into a shape of a circle. What will be the effective resistance between the ends of its diameter?
Find the currents in the resistors \(2 \, \Omega\) and \(10 \, \Omega\) in the network shown in figure, also find charge on the capacitor :
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Write Kirchhoff's laws related to electric circuit by drawing suitable circuit diagram.
Write the unit of specific resistance.
Write the Kirchhoff's law of voltage and current.
The ratio of diameters of two copper wires of same length is 2 : 1. Compare their resistances.

Establish the relation between the resistances of arms of wheatstone bridge in balance conditions.
                                                                           OR 
The ratio of lengths and masses of three wires of same metal are 3 : 2 : 1 and 1 : 2 : 3 respectively. Find the ratio of resistances of those wires.} 
 

Draw the graph between Voltage (V) and Current (I) for ohmic and non-ohmic resistances.
Derive the formula for electric field due to a uniformly charged straight wire of infinite length using Gauss's law.
Electron in the hydrogen atom is moving round the nucleus with \(6.0 \times 10^{15}\) cycle per second. What will be the value of current at a point on circular path ?
A conductor has positive charge of \(2.4 \times 10^{-18}\) coulomb. Find how much electrons are in deficit/excess on the conductor.
The unit of permittivity of vacuum is :
Write the principle of Wheatstone's Bridge. Find the current measured by the ammeter in the given circuit diagram.
Draw circuit diagram of Wheatstone’s bridge. Which are its conjugate arms?