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JEE Alternating Current PYQs with Solutions

411 previous year questions from Alternating Current (JEE Main & Advanced Physics) with answers and solutions. Numbered list, year tags, and one-tap solutions — built for serious JEE / NEET practice.

411 questionsPhysics2002–2026Answers + solutions

About Alternating Current PYQs

Alternating Current has 411 previous year questions in the Quantrex Academy JEE Main & Advanced Physics bank. The 220 questions in this list come from JEE Main (193), JEE Advanced (25) and NTA Abhyas JEE Main (2), spanning 2002 to 2026. Each question opens on its own page with the options, the correct answer and the worked solution where available.

Questions by year (this list)

  • 2026: 11
  • 2025: 11
  • 2024: 25
  • 2023: 24
  • 2022: 29
  • 2021: 42
  • 2020: 13
  • 2019: 11
  • 2018: 4
  • 2017: 3
  • 2016: 4
  • 2015: 4

Alternating Current questions with solutions

1

Consider a circuit consisting of a capacitor of capacitance C and a coil with N turns per unit length, cross sectional area S and length d , where d^2 S . There is another coil of

JEE Advanced 2026 Solution View → 2

An LCR series circuit driven with E_ rms = 90 V at frequency f_d = 30 Hz has resistance R = 80\,Ω , an inductance with inductive reactance X_L = 20.0\,Ω and capacitance with

JEE Main 2026 Solution View → 3

A series LCR circuit with R = 20\ Ω , L = 1.6 H and C = 40\ is connected to a variable frequency a.c. source. The inductive reactance at resonant frequency is _______ Ω .

JEE Main 2026 Solution View → 4

An a.c. source of angular frequency ω is connected across a resistor R and a capacitor C in series. The current is observed as I . Now the frequency of the source is changed to

JEE Main 2026 Solution View → 5

An inductor of 10 mH, capacitor of 0.1\ μ F and a resistor of 100\ Ω are connected in series across an a.c power supply 220 V, 70 Hz. The power factor of the given circuit is 0.5

JEE Main 2026 Solution View → 6

The figure given below shows an LCR series circuit with two switches S_1 and S_2 . When switch S_1 is closed keeping S_2 open, the phase difference (φ) between the current and

JEE Main 2026 Solution View → 7

An inductor stores 16 J of magnetic field energy and dissipates 32 W of thermal energy due to its resistance when an a.c. current of 2 A (rms) and frequency 50 Hz flows through

JEE Main 2026 Solution View → 8

The electric current in the circuit is given as i=i_ o (t / T) . The r.m.s current for the period t=0 to t=T is \_\_\_\_ .

JEE Main 2026 Solution View → 9

For the series L C R circuit connected with 220 ~V, 50 ~Hz a.c source as shown in the figure, the power factor is (α)/(10) . The value of α is \_\_\_\_ .

JEE Main 2026 Solution View → 10

Using a variable frequency a.c. voltage source the maximum current measured in the given LCR circuit is 50 mA for V=5 (100 t) The values of L and R are shown in the figure. The

JEE Main 2026 Solution View → 11

A capacitor C is first charged fully with potential difference of V_ 0 and disconnected from the battery. The charged capacitor is connected across an inductor having inductance L

JEE Main 2026 Solution View → 12

A circuit with an electrical load having impedance Z is connected with an AC source as shown in the diagram. The source voltage varies in time as V(t)=300 (400 t) V , where t is

JEE Advanced 2025 Solution View → 13

An inductor of reactance 100 Ω , a capacitor of reactance 50 Ω , and a resistor of resistance 50 Ω are connected in series with an AC source of 10 V , 50 Hz. Average power

JEE Main 2025 Solution View → 14

An ac current is represented as i=5 2 +10 (650 π t+(π)/(6)) Amp The r.m.s value of the current is

JEE Main 2025 Solution View → 15

For ac circuit shown in figure, R=100 k Ω and C=100 pF and the phase difference between V_ in and (V_B-V_A) is 90^ ∘ . The input signal frequency is 10^x rad / sec , where ' x '

JEE Main 2025 Solution View → 16

An inductor of self inductance 1 H connected in series with a resistor of 100 π ohm and an ac supply of 100 π volt, 50 Hz. Maximum current flowing in the circuit is ________ A.

JEE Main 2025 Solution View → 17

An alternating current is represented by the equation, i=100 2 (100 π t) ampere. The RMS value of current and the frequency of the given alternating current are

JEE Main 2025 Solution View → 18

An electric bulb rated as 100 ~W-220 ~V is connected to an ac source of rms voltage 220 V. The peak value of current through the bulb is :

JEE Main 2025 Solution View → 19

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Choke coil is simply a coil having a large inductance

JEE Main 2025 Solution View → 20

An alternating current is given by I=I_ A ω t+I_ B ω t . The r.m.s current will be

JEE Main 2025 Solution View → 21

In a series LCR circuit, a resistor of 300 Ω , a capacitor of 25 nF and an inductor of 100 mH are used. For maximum current in the circuit, the angular frequency of the ac source

JEE Main 2025 Solution View → 22

A series LCR circuit is connected to an alternating source of emf E. The current amplitude at resonant frequency is I_0 . If the value of resistance R becomes twice of its initial

JEE Main 2025 Solution View → 23

The circuit shown in the figure contains an inductor L , a capacitor C_0 , a resistor R_0 and an ideal battery. The circuit also contains two keys K_1 and K_2 . Initially, both

JEE Advanced 2024 Solution View → 24

A capacitor of reactance 4 3 Ω and a resistor of resistance 4 Ω are connected in series with an ac source of peak value 8 2 ~V . The power dissipation in the circuit is ________ W.

JEE Main 2024 Solution View → 25

A coil of negligible resistance is connected in series with 90 Ω resistor across 120 ~V, 60 ~Hz supply. A voltmeter reads 36 ~V across resistance. Inductance of the coil is :

JEE Main 2024 Solution View → 26

An alternating emf E=110 2 100 t volt is applied to a capacitor of 2 μ F , the rms value of current in the circuit is _____ mA ,

JEE Main 2024 Solution View → 27

An LCR circuit is at resonance for a capacitor C , inductance L and resistance R . Now the value of resistance is halved keeping all other parameters same. The current amplitude at

JEE Main 2024 Solution View → 28

For a given series LCR circuit it is found that maximum current is drawn when value of variable capacitance is 25 nF . If resistance of 200 Ω and 100 mH inductor is being used in

JEE Main 2024 Solution View → 29

Given below are two statements: Statement I: In an LCR series circuit, current is maximum at resonance. Statement II: Current in a purely resistive circuit can never be less than

JEE Main 2024 Solution View → 30

When a d c voltage of 100 ~V is applied to an inductor, a d c current of 5 ~A flows through it. When an ac voltage of 200 ~V peak value is connected to inductor, its inductive

JEE Main 2024 Solution View → 31

A series LCR circuit is subjected to an ac signal of 200 ~V, 50 ~Hz . If the voltage across the inductor (L=10 mH) is 31.4 ~V , then the current in this circuit is _____ .

JEE Main 2024 Solution View → 32

An ac source is connected in given series LCR circuit. The rms potential difference across the capacitor of 20 μ F is _____V.

JEE Main 2024 Solution View → 33

Match List I with List II Choose the correct answer from the options given below:

JEE Main 2024 Solution View → 34

In an ac circuit, the instantaneous current is zero, when the instantaneous voltage is maximum. In this case, the source may be connected to : A. pure inductor. B. pure capacitor.

JEE Main 2024 Solution View → 35

A alternating current at any instant is given by i=[6+ 56 (100 π t+π / 3)] A. The r m s value of the current is ________ A.

JEE Main 2024 Solution View → 36

A transformer has an efficiency of 80 % and works at 10V and 4kW . If the secondary voltage is 240V, then the current in the secondary coil is:

JEE Main 2024 Solution View → 37

A parallel plate capacitor has a capacitance C = 200pF . It is connected to 230V ac supply with an angular frequency 300rad s ^ - 1 . The rms value of conduction current in the

JEE Main 2024 Solution View → 38

In series LCR circuit, the capacitance is changed from C to 4C . To keep the resonance frequency unchanged, the new inductance should be :

JEE Main 2024 Solution View → 39

An AC voltage V = 20sin200 is applied to a series LCR circuit which drives a current I = 10sin(200 + (π)/(3)) . The average power dissipated is:

JEE Main 2024 Solution View → 40

An alternating voltage V ( t ) = 220sin100 volt is applied to a purely resistive load of 50Ω . The time taken for the current to rise from half of the peak value to the peak value

JEE Main 2024 Solution View → 41

A power transmission line feeds input power at 2 . 3kV to a step down transformer with its primary winding having 3000turns . The output power is delivered at 230V by the

JEE Main 2024 Solution View → 42

A series LR circuit connected with an ac source E = ( 25sin1000t ) V has a power factor of 1 2 . If the source of emf is changed to E = ( 20sin2000t ) V , the new power factor of

JEE Main 2024 Solution View → 43

Primary coil of a transformer is connected to 220VAC . Primary and secondary turns of the transforms are 100 and 10 respectively. Secondary coil of transformer is connected to two

JEE Main 2024 Solution View → 44

In an a.c. circuit, voltage and current are given by: V = 100sin ( 100t ) V and I = 100sin(100t + (π)/(3))mA respectively. The average power dissipated in one cycle is :

JEE Main 2024 Solution View → 45

In the given figure, the charge stored in 6 capacitor, when points A and B are joined by a connecting wire is _______ .

JEE Main 2024 Solution View → 46

A series LCR circuit with L = (100)/(π)mH, C = 10 ^ - 3 π F and R = 10Ω , is connected across an AC source of 220V, 50Hz supply. The power factor of the circuit would be ____.

JEE Main 2024 Solution View → 47

The primary side of a transformer is connected to 230V, 50Hz supply. The turn ratio of primary to secondary winding is 10: 1 . Load resistance connected to the secondary side is

JEE Main 2024 Solution View → 48

In a circuit shown in the figure, the capacitor C is initially uncharged and the key K is open. In this condition, a current of 1A flows through the 1Ω resistor. The key is closed

JEE Advanced 2023 Solution View → 49

A series LCR circuit is connected to a 45sin ( ) Volt source. The resonant angular frequency of the circuit is 10 ^ 5 rad s ^ - 1 and current amplitude at resonance is I _ 0 .

JEE Advanced 2023 Solution View → 50

Given below are two statements: Statement I : An AC circuit undergoes electrical resonance if it contains either a capacitor or an inductor. Statement II: An AC circuit containing

JEE Main 2023 Solution View → 51

Given below are two statements: Statement I : When the frequency of an AC source in a series LCR circuit increases, the current in the circuit first increases, attains a maximum

JEE Main 2023 Solution View → 52

As per the given graph, choose the correct representation for curve A and curve B Where X _ C = Reactance of pure capacitive circuit connected with A.C. source X _ L = Reactance

JEE Main 2023 Solution View → 53

Given below are two statements: Statement I: Maximum power is dissipated in a circuit containing an inductor, a capacitor and a resistor connected in series with an AC source

JEE Main 2023 Solution View → 54

A series combination of resistor of resistance 100Ω inductor of inductance 1H and capacitor of capacitance 6 . 25μ F is connected to an ac source. The quality factor of the

JEE Main 2023 Solution View → 55

An oscillating LC circuit consists of a 75mH inductor and a 1 . 2 µ F capacitor. If the maximum charge to the capacitor is 2 . 7 µ C . The maximum current in the circuit will be

JEE Main 2023 Solution View → 56

A capacitor of capacitance 150 . 0 is connected to an alternating source of emf given by E = 36sin(120 )V . The maximum value of current in the circuit is approximately equal to:

JEE Main 2023 Solution View → 57

An ideal transformer with purely resistive load operates at 12kV on the primary side. It supplies electrical energy to a number of nearby houses at 120V . The average rate of

JEE Main 2023 Solution View → 58

Match the List-I with List-II. List I List II A AC generator I Presence of both L and C B Transformer II Electromagnetic Induction C Resonance phenomenon to occur III Quality

JEE Main 2023 Solution View → 59

A series LCR circuit is connected to an ac source of 220V, 50Hz . The circuit contain a resistance R = 100Ω and an inductor of inductive reactance X _ L = 79 . 6Ω . The

JEE Main 2023 Solution View → 60

An alternating voltage source V = 260sin ( 628t ) is connected across a pure inductor of 5mH . Inductive reactance in the circuit is:

JEE Main 2023 Solution View → 61

A series LCR circuit consists of R = 80 Ω . X _ L = 100 Ω , and X _ C = 40 Ω . The input voltage is 2500cos(100 )V . The amplitude of current, in the circuit, is _____ A .

JEE Main 2023 Solution View → 62

An inductor of 0 . 5mH , a capacitor of 20μ F and resistance of 20Ω are connected in series with a 220V ac source. If the current is in phase with the emf, the amplitude of

JEE Main 2023 Solution View → 63

In the given circuit, rms value of current ( I _ rms ) through the resistor R is :

JEE Main 2023 Solution View → 64

In a series LR circuit with X _ L = R , power factor is P _ 1 . If a capacitor of capacitance C with X _ C = X _ L is added to the circuit the power factor becomes P _ 2 . The

JEE Main 2023 Solution View → 65

For the given figures, choose the correct options:

JEE Main 2023 Solution View → 66

An inductor of inductance 2μ H is connected in series with a resistance, a variable capacitor and an AC source of frequency 7kHz . The value of capacitance for which maximum

JEE Main 2023 Solution View → 67

A series LCR circuit is connected to an AC source of 220V , 50Hz . The circuit contains a resistance R = 80Ω , an inductor of inductive reactance X _ L = 70Ω , and a capacitor of

JEE Main 2023 Solution View → 68

In an LC oscillator, if values of inductance and capacitance become twice and eight times, respectively, then the resonant frequency of oscillator becomes x times its initial

JEE Main 2023 Solution View → 69

An LCR series circuit of capacitance 62 . 5nF and resistance of 50Ω , is connected to an A.C. source of frequency 2 . 0kHz . For maximum value of amplitude of current in circuit

JEE Main 2023 Solution View → 70

Three identical resistors with resistance R = 12Ω and two identical inductors with sell inductance L = 5mH are connected to an ideal battery with emf of 12V as shown in figure.

JEE Main 2023 Solution View → 71

In the circuit shown in the figure, the ratio of the quality factor and the band width is _____ s .

JEE Main 2023 Solution View → 72

Consider an LC circuit, with inductance L = 0 . 1H and capacitance C = 10 ^ - 3 F , kept on a plane. The area of the circuit is 1 m ^ 2 . It is placed in a constant magnetic field

JEE Advanced 2022 Solution View → 73

A circuit element X when connected to an AC supply of peak voltage 100V gives a peak current of 5A which is in phase with the voltage. A second element Y when connected to the

JEE Main 2022 Solution View → 74

A capacitor of capacitance 500 is charged completely using a de supply of 100V . It is now connected to an inductor of inductance 50mH to form an LC circuit. The maximum current

JEE Main 2022 Solution View → 75

An alternating emf E = 440sin100 is applied to a circuit containing an inductance of 2 π H . If an a.c. ammeter is connected in the circuit, its reading will be :

JEE Main 2022 Solution View → 76

A coil of inductance 1H and resistance 100Ω is connected to a battery of 6V . Determine approximately : (a) The time elapsed before the current acquires half of its steady-state

JEE Main 2022 Solution View → 77

A transformer operating at primary voltage 8kV and secondary voltage 160V serves a load of 80kW . Assuming the transformer to be ideal with purely resistive load and working on

JEE Main 2022 Solution View → 78

The equation of current in a purely inductive circuit is 5sin(49 - 30 °) . If the inductance is 30mH then the equation for the voltage across the inductor, will be

JEE Main 2022 Solution View → 79

The frequencies at which the current amplitude in an LCR series circuit becomes 1 2 times its maximum value, are 212rad s ^ - 1 and 232rad s ^ - 1 . The value of resistance in the

JEE Main 2022 Solution View → 80

A series LCR circuit has L = 0 . 01H, R = 10Ω and C = 1 and it is connected to ac voltage of amplitude ( V _ m )50V . At frequency 60 % lower than resonant frequency, the

JEE Main 2022 Solution View → 81

A direct current of 4A and an alternating current of peak value 4A flow through resistance of 3Ω and 2Ω respectively. The ratio of heat produced in the two resistances in same

JEE Main 2022 Solution View → 82

To light, a 50W, 100V lamp is connected, in series with a capacitor of capacitance 50 π x , with 200V, 50HzAC source. The value of x will be _____ .

JEE Main 2022 Solution View → 83

The effective current I in the given circuit at very high frequencies will be _____ A .

JEE Main 2022 Solution View → 84

When you walk through a metal detector carrying a metal object in your pocket, it raises an alarm. This phenomenon works on

JEE Main 2022 Solution View → 85

To increase the resonant frequency in series LCR circuit,

JEE Main 2022 Solution View → 86

The RMS value of conduction current in a parallel plate capacitor is 6 . 9 . The capacity of this capacitor, if it is connected to 230V AC supply with an angular frequency of

JEE Main 2022 Solution View → 87

An inductor of 0 . 5mH , a capacitor of 200μ F and a resistor of 2Ω are connected in series with a 220V ac source. If the current is in phase with the emf, the frequency of ac

JEE Main 2022 Solution View → 88

For a series LCR circuit, I vs ω curve is shown (a) To the left of ω _ r , the circuit is mainly capacitive. (b) To the left of ω _ r , the circuit is mainly inductive. (c) At ω _

JEE Main 2022 Solution View → 89

In the given circuit, the magnitude of V _ L and V _ C are twice that of V _ R . Given that f = 50Hz , the inductance of the coil is (1)/(Kπ)mH . The value of K is _____ .

JEE Main 2022 Solution View → 90

An AC source is connected to an inductance of 100mH , a capacitance of 100 and a resistance of 120Ω as shown in figure. The time in which the resistance having a thermal capacity

JEE Main 2022 Solution View → 91

A telegraph line of length 100km has a capacity of 0 . 01 km ^ - 1 and it carries an alternating current at 0 . 5 kilo cycle per second. If minimum impedance is required, then the

JEE Main 2022 Solution View → 92

The current flowing through an ac circuit is given by I = 5sin(120 )A . How long will the current take to reach the peak value starting from zero?

JEE Main 2022 Solution View → 93

A 110V, 50Hz, AC source is connected in the circuit (as shown in figure). The current through the resistance 55Ω , at resonance in the circuit, will be _____ A .

JEE Main 2022 Solution View → 94

A sinusoidal voltage V(t) = 210sin3000t volt is applied to a series LCR circuit in which L = 10mH, C = 25μ F and R = 100Ω . The phase difference (Φ) between the applied voltage

JEE Main 2022 Solution View → 95

In a series LCR circuit, the inductance, capacitance and resistance are L = 100mH , C = 100 and R = 10Ω respectively. They are connected to an AC source of voltage 220V and

JEE Main 2022 Solution View → 96

Match List - I with List - II. List-I List-II (A) AC generator (I) Detects the presence of current in the circuit (B) Galvanometer (II) Converts mechanical energy into electrical

JEE Main 2022 Solution View → 97

If wattless current flows in the AC circuit, then the circuit is :

JEE Main 2022 Solution View → 98

Given below are two statements : Statement-I: The reactance of an ac circuit is zero. It is possible that the circuit contains a capacitor and an inductor. Statement-II: In ac

JEE Main 2022 Solution View → 99

A resistance of 40Ω is connected to a source of alternating current rated 220V, 50Hz . Find the time taken by the current to change from its maximum value to the rms value :

JEE Main 2022 Solution View → 100

As shown in the figure an inductor of inductance 200mH is connected to an AC source of emf 220V and frequency 50Hz . The instantaneous voltage of the source is 0V when the peak

JEE Main 2022 Solution View → 101

In a circuit, a metal filament lamp is connected in series with a capacitor of capacitance C μ F across a 200 ~V, 50 ~Hz supply. The power consumed by the lamp is 500 ~W while the

JEE Advanced 2021 Solution View → 102

In a circuit, a metal filament lamp is connected in series with a capacitor of capacitance C μ F across a 200 ~V, 50 ~Hz supply. The power consumed by the lamp is 500 ~W while the

JEE Advanced 2021 Solution View → 103

At very high frequencies, the effective impedance of the given circuit will be _________ Ω .

JEE Main 2021 Solution View → 104

In an ac circuit, an inductor, a capacitor and a resistor are connected in series with X _ L = R = X _ C . Impedance of this circuit is :

JEE Main 2021 Solution View → 105

An AC circuit has an inductor and a resistor of resistance R in series, such that X _ L = 3R . Now, a capacitor is added in series such that X _ C = 2R . the ratio of the new

JEE Main 2021 Solution View → 106

The alternating current is given by, i = \ 42 sin((2π)/(T)t) + 10\ A . The R.M.S. value of this current is __________ A .

JEE Main 2021 Solution View → 107

In the given circuit the AC source has ω = 100rad s ^ - 1 . Considering the inductor and capacitor to be ideal, what will be the current I flowing through the circuit?

JEE Main 2021 Solution View → 108

A series LCR circuit driven by 300V at a frequency of 50Hz contains a resistance R = 3kΩ , an inductor of inductive reactance X _ L = 250πΩ and an unknown capacitor. The value of

JEE Main 2021 Solution View → 109

An inductor coil stores 64J of magnetic field energy and dissipates energy at the rate of 640W when a current of 8A is passed through it. If this coil is joined across an ideal

JEE Main 2021 Solution View → 110

A 100Ω resistance, a 0 . 1 capacitor and an inductor are connected in series across a 250V supply at variable frequency. Calculate the value of inductance of inductor at which

JEE Main 2021 Solution View → 111

A 0 . 07H inductor and a 12Ω resistor are connected in series to a 220V, 50Hz AC source. The approximate current in the circuit and the phase angle between current and source

JEE Main 2021 Solution View → 112

A 10Ω resistance is connected across 220V - 50Hz AC supply. The time taken by the current to change from its maximum value to the rms value is:

JEE Main 2021 Solution View → 113

Two circuits are shown in figure ( a ) and ( b ) . At a frequency of _______ rad s ^ - 1 the average power dissipated in one cycle will be the same in both the circuits.

JEE Main 2021 Solution View → 114

An inductor of 10mH is connected to a 20V battery through a resistor of 10kΩ and a switch. After a long time, when maximum current is set up in the circuit, the current is

JEE Main 2021 Solution View → 115

In a circuit consisting of a capacitance and a generator with alternating emf, E _ g = E _ go sin , V _ C and I _ C are the voltage and current. Correct phasor diagram for such

JEE Main 2021 Solution View → 116

Match List-I with List-II. List - I List - II (a) > (1)/( ) (i) Current is in phase with emf (b) = (1)/( ) (ii) Current lags behind the applied emf (c) (iii) Maximum current

JEE Main 2021 Solution View → 117

For a series LCR circuit with R = 100Ω, L = 0 . 5mH and C = 0 . 1pF connected across 220V - 50Hz AC supply, the phase angle between current and supplied voltage and the nature of

JEE Main 2021 Solution View → 118

A series LCR circuit of R = 5Ω, L = 20mH and C = 0 . 5 is connected across an AC supply of 250V, having variable frequency. The power dissipated at resonance condition is ________

JEE Main 2021 Solution View → 119

AC voltage V ( t ) = 20sin of frequency 50Hz is applied to a parallel plate capacitor. The separation between the plates is 2mm and the area is 1 m ^ 2 . The amplitude of the

JEE Main 2021 Solution View → 120

In an LCR series circuit, an inductor 30mH and a resistor 1Ω are connected to an AC source of angular frequency 300rad s ^ - 1 . The value of capacitance for which the current

JEE Main 2021 Solution View →
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Alternating Current in other exams

NEET Alternating Current (366)BITSAT Alternating Current (20)