JEE Main 2020 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 8 January 2020, Shift 2, Physics Q9

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

A transverse wave travels on a taut steel wire with a velocity of

v

when tension in it is

2.06\times10^{4}\ \mathrm{N}

. When the tension is changed to T, the velocity changed to

v/2

. The value of T is close to :

(1) $2.50\times10^{4}\ \mathrm{N}$
(2) $5.15\times10^{3}\ \mathrm{N}$ Official answer
(3) $30.5\times10^{4}\ \mathrm{N}$
(4) $10.2\times10^{2}\ \mathrm{N}$

Official answer

Option 2

NTA final key (Jan 2020).

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

Same idea in other shifts

Asked 9× in all

8 Apr 2025, Shift 2 · Q34Two strings with circular cross section and made of same material, are stretched to have same amount of tension. A transverse wave is then…EasySingle correct
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11 Apr 2023, Shift 2 · Q51A wire of density $8\times10^{3}\ \mathrm{kg/m^3}$ is stretched between two clamps $0.5\ \mathrm{m}$ apart. The extension developed in the…MediumNumerical value
15 Apr 2023, Shift 1 · Q51The fundamental frequency of vibration of a string stretched between two rigid support is 50 Hz. The mass of the string is 18 g and its…EasyNumerical value
28 Jul 2022, Shift 1 · Q39In the wave equation $y=0.5\sin\frac{2\pi}{\lambda}(400\,t-x)\ \mathrm{m}$ the velocity of the wave will be :EasySingle correct
29 Jul 2022, Shift 2 · Q56The speed of a transverse wave passing through a string of length 50 cm and mass 10 g is 60 $\mathrm{ms^{-1}}$ . The area of cross-section…MediumNumerical value
25 Feb 2021, Shift 2 · Q23The percentage increase in the speed of transverse waves produced in a stretched string if the tension is increased by 4%, will be…EasyNumerical value
26 Feb 2021, Shift 1 · Q24The mass per unit length of a uniform wire is 0.135 g/cm. A transverse wave of the form $y=-0.21\sin(x+30t)$ is produced in it, where $x$ …MediumNumerical value

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.