JEE Main 2020 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 3 September 2020, Shift 1, Physics Q15

Question 15 of 75 in this shift, Physics question 15 of 25.

A 750 Hz, 20 V (rms) source is connected to a resistance of 100

\Omega

, an inductance of 0.1803 H and a capacitance of 10

\mu

F all in series. The time in which the resistance (heat capacity 2 J/°C) will get heated by 10°C. (assume no loss of heat to the surroundings) is close to :

(1)348 sOfficial answer
(2)245 s
(3)365 s
(4)418 s

Official answer

Option 1

NTA final key (Sep 2020).

Chapter: Alternating Current
Topic: Phasor Diagrams
Idea tested: Impedance Triangle Construction

Same idea in other shifts

Asked 9× in all

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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.