JEE Main 2021 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 24 February 2021, Shift 1, Physics Q23

Question 23 of 90 in this shift, Physics question 23 of 30, Section B.

A ball with a speed of 9 m/s collides with another identical ball at rest. After the collision, the direction of each ball makes an angle of

30^\circ

with the original direction. The ratio of velocities of the balls after collision is

x:y

, where

x

is __________ .

Official answer

NTA final key.

Chapter: Work, Energy and Power
Topic: Collisions
Idea tested: Oblique Collisions

Same idea in other shifts

Asked 6× in all

31 Aug 2021, Shift 1 · Q20A body of mass M moving at speed $V_0$ collides elastically with a mass 'm' at rest. After the collision, the two masses move at angles…HardSingle correct
8 Jan 2020, Shift 1 · Q22A body A, of mass m = 0.1 kg has an initial velocity of $3\hat{i}$ ms $^{-1}$ . It collides elastically with another body, B of the same…MediumNumerical value
2 Sep 2020, Shift 1 · Q3A particle of mass $m$ with an initial velocity $u\hat{i}$ collides perfectly elastically with a mass $3m$ at rest. It moves with a…MediumSingle correct
2 Sep 2020, Shift 2 · Q21A particle of mass m is moving along the x-axis with initial velocity u $\hat{i}$ . It collides elastically with a particle of mass 10 m at…HardNumerical valueHas a figure
6 Sep 2020, Shift 2 · Q4Particle A of mass $m_1$ moving with velocity $\left(\sqrt{3}\hat{i}+\hat{j}\right)\,\mathrm{ms^{-1}}$ collides with another particle B of…MediumSingle correct

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.