JEE Main 2020 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 3 September 2020, Shift 1, Physics Q9

Question 9 of 75 in this shift, Physics question 9 of 25.

A uniform thin rope of length 12 m and mass 6 kg hangs vertically from a rigid support and a block of mass 2 kg is attached to its free end. A transverse short wave-train of wavelength 6 cm is produced at the lower end of the rope. What is the wavelength of the wavetrain (in cm) when it reaches the top of the rope ?

(1)6
(2)3
(3)9
(4)12Official answer

Official answer

Option 4

NTA final key (Sep 2020).

Chapter: Waves
Topic: Waves on Strings
Idea tested: Wave Speed on a Hanging String

Same topic in other shifts

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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.