Zaymiey

⚛️ Physics  ·  Alternating Current  ·  NEET & JEE

The peak value of an alternating current is 10 A. Its rms value is:

Answer: 7.07 A.

  • A 5 A
  • B 7.07 A
  • C 10 A
  • D 14.1 A

Correct answer: B. 7.07 A

Explanation: I<sub>rms</sub> = I₀/√2 = 10/1.414 ≈ 7.07 A.

V and I Phase Relationships in AC CircuitsPure Inductor: I lags V by 90°VIPure Capacitor: I leads V by 90°VIMemory aid "ELI the ICE man": in an inductor (L) E(V) leads I; in a capacitor (C) I leads E(V)For a pure resistor, V and I stay perfectly in phase (no lag or lead at all)

In a pure inductor the current lags the voltage by 90° (energy is briefly stored in the magnetic field before current responds); in a pure capacitor the current leads the voltage by 90° (current must flow to build up charge before voltage rises) - the mnemonic "ELI the ICE man" keeps these straight.

Concept context

AC circuits, impedance, LCR series circuit, resonance, transformers, and power factor.

Read the full Alternating Current notes →