Karnataka 2nd PUC Physics Chapter 7 Important Questions: Alternating Current

Karnataka 2nd PUC Physics Chapter 7 Important Questions 2027 covers Alternating Current concepts, formulas, numerical problems, and circuit-based questions. Practise questions on RMS values, reactance, LCR circuits, resonance, power factor, transformers, and LC oscillations.

The chapter on Alternating Current includes concepts related to AC voltage and current, resistors, inductors, capacitors, series LCR circuits, resonance, transformers, and LC oscillations. These concepts involve both theoretical questions and numerical problems.

The Karnataka 2nd PUC Physics Chapter 7 Important Questions provide focused practice on these concepts. Solving them can help you revise formulas, understand circuit behaviour, practise calculations, and identify topics that need further revision.

Karnataka 2nd PUC Physics Chapter 7 Important Questions

Practising questions from Alternating Current helps you revise the concepts and formulas covered in the chapter. The selected questions below are based on the chapter practice set and previous-year questions included in the study material.

Q1. When the current changes continuously in magnitude and periodically in direction, several times per second, the current is known as the

(A) direct current
(B) induced current
(C) displacement current
(D) alternating current

Q2. Current through a circuit is given by

I = vm / ωL. cos⁡(ωt) + constant

In the given equation, the integration constant has the dimension of:

(A) Resistor
(B) Current
(C) Voltage
(D) Inductor

Q3. In an AC circuit, the current lags behind the voltage by π/2\pi/2. The components of the circuit are:

(A) RR and LL
(B) LL and CC
(C) RR and CC
(D) Only R

Q4. When an AC voltage of 220 V is applied to the capacitor CC:

(A) The maximum voltage between plates is 220 V
(B) The current is in phase with the applied voltage
(C) The charge on the plates is in phase with the applied voltage
(D) Power delivered to the capacitor is zero

Q5. As the frequency of an AC circuit increases, the current first increases and then decreases. What combination of circuit elements is most likely to comprise the circuit?

(A) Inductor and capacitor
(B) Resistor and inductor
(C) Resistor and capacitor
(D) Resistor, inductor and capacitor

Q6. A capacitor and an inductance coil are connected in separate AC circuits with a bulb glowing in both circuits. The bulb glows more brightly when:

(A) The number of turns in the inductance coil
(B) An iron rod is introduced into the inductance coil
(C) A dielectric is introduced into the gap between the plates of the capacitor
(D) Separation between the plates of the capacitor is increased

Q7: Resonant circuits are used in:

(A) The tuning mechanism of a radio
(B) The tuning mechanism of TV set
(C) Both radio and TV tuning circuits
(D) Mobile network tuner

Q8: Which of the following components of a L-C-R circuit, with AC supply, do not dissipate energy?

(A) L, C
(B) R, C
(C) L, R
(D) L C R

Q9: The value of emf in the secondary coil of a transformer depends on:

(A) The number of turns
(B) Voltage
(C) Material used
(D) Induced flux

Q10: When an AC voltage of 220 V is applied to the capacitor C

(A) the maximum voltage between plates is 220 V
(B) the current is in phase with the applied voltage
(C) the charge on the plates is in phase with the applied voltage
(D) power delivered to the capacitor is zero

These questions cover some of the recurring concepts in the chapter, including RMS current, phase difference, resonance, and transformers. The study material also contains additional practice questions and previous-year questions for further practice.

Karnataka 2nd PUC Physics Chapter 7 Alternating Current PDF

The Karnataka 2nd PUC Physics Chapter 7 Important Questions PDF can be used for offline practice and revision. It contains practice questions covering AC circuits, LCR circuits, resonance, power factor, transformers, and LC oscillations.

The PDF also includes previous-year questions from KCET 2020 onwards. These questions provide additional practice on concepts such as resonant frequency, power factor, transformer efficiency, RMS values, and power transmission.

Important Topics in Karnataka 2nd PUC Physics: Alternating Current

You should revise the main concepts and formulas before attempting the questions. Key areas include:

• AC Voltage and Current: Revise sinusoidal voltage and current equations, RMS values, peak values, frequency, and average value over a complete cycle.

• Resistor, Inductor and Capacitor: Understand the phase relationship between voltage and current in each component. For a resistor, voltage and current are in phase. In an inductor, current lags voltage while in a capacitor, current leads voltage .
  Reactance: Practise the expressions for inductive and capacitive reactance and understand how they change with frequency.

• Series LCR Circuit: Revise impedance, phase angle, current, and the relationship between resistance and reactance.

• Resonance: Understand the resonance condition, resonant frequency, impedance at resonance, and maximum current.

• Power in AC Circuits: Revise average power, power factor, and the concept of wattless current.

• Transformers: Understand the turns ratio, voltage transformation, current relation, and transformer losses.

• LC Oscillations: Revise the energy exchange between the capacitor and inductor and the expression for the frequency of oscillation.

How to Prepare for Karnataka 2nd PUC Physics Alternating Current

You can combine formula revision with MCQ practice to prepare for Alternating Current effectively. A simple approach is:

• Revise the basic concepts: Start with AC voltage and current, RMS values, and the phase relationship between voltage and current.

• Practise circuit formulas: Solve questions based on (X_L), (X_C), impedance, phase angle, and resonance. This will help you become comfortable with circuit calculations.

• Focus on resonance: Practise questions involving resonant frequency, impedance, current, and changes in (L), (C), or (R).

• Solve numerical problems: Work through AC Circuit Important Questions involving RMS values, reactance, impedance, power factor, and transformers. Write the formula first and substitute the given values carefully.

• Revise derivations: Practise the Alternating Current Important Derivations related to RMS values, reactance, impedance, resonance, and other derivations included in your prescribed syllabus.

• Attempt questions independently: Solve the questions without looking at the answer first. Then check your response and revise the concept if you make an error.

Karnataka 2nd PUC Physics Chapter 7 Important Questions 2027 covers RMS values, AC circuits, reactance, LCR circuits, resonance, power factor, transformers, and LC oscillations. Regular practice of these questions can help you revise formulas, solve numerical problems, and strengthen your understanding of Alternating Current.

Related Resources:

• Karnataka 2nd PUC Mid Term Time Table 2026 

• Karnataka 2nd PUC Mid Term Question Paper

• Karnataka 2nd PUC Previous Year Question Paper 

• Karnataka 2nd PUC Exam Pattern 2027

• Karnataka 2nd PUC Syllabus 2026-27

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