JEE Main 27 August 2021, Shift 1, Physics Q28

Question 28 of 90 in this shift, Physics question 28 of 30, Section B.

The alternating current is given by

i=\left\{\sqrt{42}\ \sin\left(\frac{2\pi}{\mathrm{T}}\mathrm{t}\right)+10\right\}

A The r.m.s. value of this current is __________ A.

Official answer

NTA final key.

Chapter: Alternating Current
Topic: RMS and Peak Values
Idea tested: RMS of DC and AC Superposition

Same idea in other shifts

Asked 2× in all

7 Apr 2025, Shift 1 · Q35An ac current is represented as $i = 5\sqrt{2} + 10\cos\left(650\pi t + \frac{\pi}{6}\right)$ Amp The r.m.s value of the current isEasySingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.