JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumApplication

JEE Main 4 August 2021, Shift 1, Physics Q11

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

A piece of wood has dimensions

\ell

, b and h. Its relative density is ‘d’. It is floating in water such that the side ‘h’ is vertical. If it is pushed down gently and released, the angular frequency will be

(1) $\sqrt{\frac{g}{dh}}$ Official answer
(2) $\sqrt{\frac{\ell bg}{dh}}$
(3) $\sqrt{\frac{dg}{h}}$
(4) $\sqrt{\frac{dg}{\ell bh}}$

Official answer

Option 1

NTA final key.

Chapter: Oscillations
Topic: Fluid Statics
Idea tested: SHM of a Floating Body

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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.