Alternating Current: Class 12 Physics (MP Board) important questions and practice
Alternating Current is chapter 7 of 14 in MP Board Class 12 Physics. Below are the topics the paper draws from, the question types that come up again and again, and a free practice test on this chapter alone.
Topics in this chapter
- AC voltage applied to a resistor; rms and peak values
- Phasors; AC through an inductor and a capacitor (reactance)
- Series LCR circuit: impedance, phase angle and phasor diagram
- Resonance in a series LCR circuit; sharpness and quality factor
- Power in AC circuits: power factor and wattless current
- Transformers: principle, construction, energy losses
What examiners usually ask
- Derive the expression for the impedance of a series LCR circuit using a phasor diagram and find the condition for resonance
- Explain the principle and working of a transformer and list the sources of energy loss
- A 100 ohm resistor is connected to a 220 V, 50 Hz supply; find the rms current and the net power consumed over a full cycle
Exam tip
The LCR phasor diagram derivation with Z = root(R^2 + (XL - XC)^2) and the transformer question appear almost every year; also know that the average power over a cycle in a pure inductor or capacitor is zero (wattless current).
Alternating Current on other boards and exams
Frequently asked questions
What are the important questions from Alternating Current for MP Board Class 12?
The question types listed above repeat most often in MP Board Class 12 Physics papers for this chapter. Practise them with the chapter test and then attempt them inside a full previous-year paper under time.
Is Alternating Current in the MP Board Class 12 Physics syllabus?
Yes. Alternating Current is part of the current MP Board Class 12 Physics syllabus, as listed on this site from the prescribed textbook.
Can I practise Alternating Current MCQs in Hindi?
Yes. The chapter test and explanations are available in Hindi and English, with an AI doubt solver for any question.