Current Electricity

27 JEE Main questions · Physics

Cells and circuits

PhysicsJEE Main 21 Jan 2026, Shift 1·Q22·Numerical·Easy–moderate
Open
The heat generated in 1 minute between points A and B in the given circuit, when a battery of 9 V with internal resistance of $1\ \Omega$ is connected across these points is J.
PhysicsJEE Main 21 Jan 2026, Shift 2·Q2·MCQ·Moderate
Open
The charge stored by the capacitor C in the given circuit in the steady state is $\mu$ C.
1. (1)12.5
2. (2)10
3. (3)7.5
4. (4)5
PhysicsJEE Main 21 Jan 2026, Shift 2·Q3·MCQ·Easy–moderate
Open
The total length of potentiometer wire AB is 50 cm in the arrangement as shown in figure. If P is the point where the galvanometer shows zero reading then the length AP is cm.
1. (1)15
2. (2)30
3. (3)25
4. (4)20
PhysicsJEE Main 21 Jan 2026, Shift 2·Q10·MCQ·Easy
Open
A battery with EMF E and internal resistance r is connected across a resistance R. The power consumption in R will be maximum when :
1. (1) $R = 2r$
2. (2) $R = \dfrac{r}{2}$
3. (3) $R = \sqrt{2}\,r$
4. (4) $R = r$
PhysicsJEE Main 22 Jan 2026, Shift 1·Q6·MCQ·Moderate
Open
A meter bridge with two resistances $R_1$ and $R_2$ as shown in figure was balanced (null point) at 40 cm from the point P. The null point changed to 50 cm from the point P, when $16\ \Omega$ resistance is connected in parallel to $R_2$ . The values of resistances $R_1$ and $R_2$ are .
1. (1) $R_2 = 16\ \Omega,\ R_1 = \dfrac{16}{3}\ \Omega$
2. (2) $R_2 = 4\ \Omega,\ R_1 = \dfrac{4}{3}\ \Omega$
3. (3) $R_2 = 8\ \Omega,\ R_1 = \dfrac{16}{3}\ \Omega$
4. (4) $R_2 = 12\ \Omega,\ R_1 = \dfrac{12}{3}\ \Omega$
PhysicsJEE Main 24 Jan 2026, Shift 1·Q12·MCQ·Moderate
Open
Two resistors $2\ \Omega$ and $3\ \Omega$ are connected in the gaps of bridge as shown in figure. The null point is obtained with the contact of jockey at some point on wire XY. When an unknown resistor is connected in parallel with $3\ \Omega$ resistor, the null point is shifted by 22.5 cm toward Y. The resistance of unknown resistor is $\Omega$ . (Take the length of the wire XY as 100 cm)
1. (1)3
2. (2)2
3. (3)4
4. (4)1
We corrected a printing error in the original paper
Assumption “(Take the length of the wire XY as 100 cm)” added; the source leaves it unstated.
PhysicsJEE Main 24 Jan 2026, Shift 2·Q23·Numerical·Moderate
Open
In a meter bridge experiment to determine the value of unknown resistance, first the resistances $2\ \Omega$ and $3\ \Omega$ are connected in the left and right gaps of the bridge and the null point is obtained at a distance $l$ cm from the left. Now when an unknown resistance $x\ \Omega$ is connected in parallel to $3\ \Omega$ resistance, the null point is shifted by 10 cm to the right of wire. The value of unknown resistance $x$ is $\Omega$ .
PhysicsJEE Main 28 Jan 2026, Shift 1·Q3·MCQ·Moderate
Open
In the potentiometer, when the cell in the secondary circuit is shunted with $4\ \Omega$ resistance, the balance is obtained at the length 120 cm of wire. Now when the same cell is shunted with $12\ \Omega$ resistance, the balance is shifted to a length of 180 cm. The internal resistance of cell is $\Omega$ .
1. (1)3
2. (2)4
3. (3)12
4. (4)6
We corrected a printing error in the original paper
Source printed “the same cell in shunted”.
PhysicsJEE Main 28 Jan 2026, Shift 1·Q13·MCQ·Easy–moderate
Open
For the two cells having same EMF E and internal resistance $r$ , the current passing through the external resistor $6\ \Omega$ is same when both the cells are connected either in parallel or in series. The value of internal resistance $r$ is $\Omega$ .
1. (1)3
2. (2)4
3. (3)9
4. (4)6
PhysicsJEE Main 28 Jan 2026, Shift 1·Q25·Numerical·Moderate
Open
The equivalent resistance between the points $A$ and $B$ in the following circuit is $\dfrac{x}{5}\,\Omega$ . The value of $x$ is .
PhysicsJEE Main 28 Jan 2026, Shift 2·Q6·MCQ·Easy–moderate
Open
A wheatstone bridge is initially at room temperature and all arms of the bridge have same value of resistances ( $R_1 = R_2 = R_3 = R_4$ ). When $R_3$ resistance is heated to some temperature, its resistance value has gone up by 10%. The potential difference $(V_a - V_b)$ (after $R_3$ is heated) is V.
1. (1)1.05
2. (2)0
3. (3)0.95
4. (4)2
PhysicsJEE Main 4 Apr 2026, Shift 1·Q18·MCQ·Moderate
Open
The voltage and the current between A and B points shown in the circuit are .
1. (1)24 V, 12 A
2. (2)24 V, 4 A
3. (3)18 V, 12 A
4. (4)27 V, 4 A
PhysicsJEE Main 5 Apr 2026, Shift 1·Q9·MCQ·Moderate
Open
Refer to the figure given below. The values of $I_1$ , $I_2$ and $I_3$ are .
1. (1) $I_1 = 2.5$ A, $I_2 = 1.875$ A, $I_3 = 1.875$ A
2. (2) $I_1 = 1.875$ A, $I_2 = 2.5$ A, $I_3 = 1.875$ A
3. (3) $I_1 = 1.875$ A, $I_2 = 1.875$ A, $I_3 = 2.5$ A
4. (4) $I_1 = 2.5$ A, $I_2 = 2.5$ A, $I_3 = 1.875$ A
PhysicsJEE Main 5 Apr 2026, Shift 1·Q13·MCQ·Moderate
Open
Refer to the figure given below, current between terminals A and B is A.
1. (1)12.5
2. (2)1.25
3. (3)7.5
4. (4)5
PhysicsJEE Main 5 Apr 2026, Shift 2·Q12·MCQ·Easy–moderate
Open
Under steady state condition the potential difference across the capacitor in the circuit isV.
1. (1)0.5
2. (2)1.5
3. (3)0
4. (4)2
PhysicsJEE Main 5 Apr 2026, Shift 2·Q24·Numerical·Easy–moderate
Open
When an external resistance of $5\ \Omega$ is connected across terminals of a cell, a current of 0.25 A flows through it. When the $5\ \Omega$ resistor is replaced by a $2\ \Omega$ resistor, a current of 0.5 A flows through it. The internal resistance of the cell is $\Omega$ .
PhysicsJEE Main 6 Apr 2026, Shift 1·Q21·Numerical·Moderate
Open
Refer to the circuit diagram given below. The heat generated across the $6\ \Omega$ resistance in 100 second is $\dfrac{\alpha}{100}$ J. The value of $\alpha$ is . (Nearest integer)
PhysicsJEE Main 6 Apr 2026, Shift 2·Q24·Numerical·Moderate
Open
Two cells of emfs 1 V and 2 V and internal resistances $2\ \Omega$ and $1\ \Omega$ , respectively connected in parallel, gave current of 1 A through an external resistance. If the polarity of one cell is reversed, then value of current through the external resistance will be $\dfrac{\alpha}{5}$ A. The value of $\alpha$ is .
We corrected a printing error in the original paper
Source printed “internal reseistance”.

Current and resistance

PhysicsJEE Main 21 Jan 2026, Shift 2·Q15·MCQ·Easy–moderate
Open
Two known resistances of R $\Omega$ and 2R $\Omega$ and one unknown resistance X $\Omega$ are connected in a circuit as shown in the figure. If the equivalent resistance between points A and B in the circuit is X $\Omega$ , then the value of X is $\Omega$ .
1. (1) $\left(\sqrt3 - 1\right)R$
2. (2) $R$
3. (3) $2\left(\sqrt3 - 1\right)R$
4. (4) $\left(\sqrt3 + 1\right)R$
We corrected a printing error in the original paper
Source printed “Two known resistance”; “and and”.
PhysicsJEE Main 22 Jan 2026, Shift 2·Q11·MCQ·Easy–moderate
Open
An electric power line having total resistance of $2\ \Omega$ , delivers 1 kW of power of 250 V. The percentage efficiency of transmission line is .
1. (1)96.9
2. (2)86.5
3. (3)100
4. (4)92.5
PhysicsJEE Main 22 Jan 2026, Shift 2·Q24·Numerical·Easy–moderate
Open
A cylindrical conductor of length 2 m and area of cross-section $0.2\ \mathrm{mm^2}$ carries an electric current of 1.6 A when its ends are connected to a 2 V battery. Mobility of electrons in the conductor is $\alpha\times10^{-3}\ \mathrm{m^2/V.s}$ . The value of $\alpha$ is : (electron concentration $= 5\times10^{28}/\mathrm{m^3}$ and electron charge $= 1.6\times10^{-19}$ C)
PhysicsJEE Main 23 Jan 2026, Shift 1·Q9·MCQ·Easy–moderate
Open
A wire of uniform resistance $\lambda\ \Omega$ /m is bent into a circle of radius r and another piece of wire with length 2r is connected between points A and B (AOB) as shown in figure. The equivalent resistance between points A and B is $\Omega$ .
1. (1) $\dfrac{3\pi\lambda r}{8}$
2. (2) $(\pi + 1)\,2r\lambda$
3. (3) $\dfrac{6\pi\lambda r}{3\pi + 16}$
4. (4) $2\pi\lambda r$
PhysicsJEE Main 24 Jan 2026, Shift 1·Q5·MCQ·Easy–moderate
Open
Two resistors of $100\ \Omega$ each are connected in series with a 9 V battery. A voltmeter of $400\ \Omega$ resistance is connected to measure the voltage drop across one of the resistors. The voltmeter reading is V.
1. (1)3
2. (2)4.5
3. (3)4
4. (4)2
PhysicsJEE Main 24 Jan 2026, Shift 2·Q1·MCQ·Easy–moderate
Open
The reading of the ammeter (A) in steady state in the following circuit (assuming negligible internal resistance of the ammeter) is A.
1. (1)2
2. (2)1
3. (3)1/2
4. (4)0
PhysicsJEE Main 24 Jan 2026, Shift 2·Q4·MCQ·Moderate
Open
A regular hexagon is formed by six wires each of resistance $r\ \Omega$ and the corners are joined to centre by wires of same resistance. If the current enters at one corner and leaves at the opposite corner, the equivalent resistance of the hexagon between the two opposite corners will be
1. (1) $\dfrac45 r$
2. (2) $\dfrac58 r$
3. (3) $\dfrac34 r$
4. (4) $\dfrac35 r$
PhysicsJEE Main 2 Apr 2026, Shift 2·Q13·MCQ·Easy–moderate
Open
Two resistors of $200\ \Omega$ and $400\ \Omega$ are connected in series with a battery of 100 V. A bulb rated at 200 V, 100 W is connected across the $400\ \Omega$ resistance. The potential drop across the bulb is V.
1. (1)25
2. (2)50
3. (3)66.6
4. (4)100
PhysicsJEE Main 8 Apr 2026, Shift 2·Q24·Numerical·Moderate
Open
The stored charge in the capacitor in steady state of the following circuit is $\mu$ C.