JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyApplication

JEE Main 26 February 2021, Shift 1, Physics Q11

Question 11 of 90 in this shift, Physics question 11 of 30, Section A.

If two similar springs each of spring constant

\mathrm{K_1}

are joined in series, the new spring constant and time period would be changed by a factor :

(1) $\frac{1}{2},\ \sqrt{2}$ Official answer
(2) $\frac{1}{4},\ 2\sqrt{2}$
(3) $\frac{1}{2},\ 2\sqrt{2}$
(4) $\frac{1}{4},\ \sqrt{2}$

Official answer

Option 1

NTA final key.

Chapter: Oscillations
Topic: SHM Equations
Idea tested: Springs in Series

Same idea in other shifts

Asked 4× 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.