JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 25 July 2021, Shift 1, Physics Q3

Question 3 of 90 in this shift, Physics question 3 of 30, Section A.

Water droplets are coming from an open tap at a particular rate. The spacing between a droplet observed at

4^{\mathrm{th}}

second after its fall to the next droplet is 34.3 m. At what rate the droplets are coming from the tap ? (Take g = 9.8 m/s

^2

)

(1)1 drop/secondOfficial answer
(2)2 drops/second
(3)3 drops/2 seconds
(4)1 drop/7 seconds

Official answer

Option 1

NTA final key.

Chapter: Motion in a Straight Line
Topic: Kinematics in 1D
Idea tested: Water Drops from a Tap

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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 42 of the 174 JEE Main shifts held from 2017 to 2026.