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QJEEM21Ph030c: JEE Main 2021 Physics - Class 11 JEEM21Ph030c Solution: Two billiard balls of equal mass 30g strike a rigid wall with…

Two billiard balls of equal mass 30g strike a rigid wall with same speed of 108 kmph (as shown) but at different angles. If the balls get reflected with the same speed then the ratio of the magnitude of impulses imparted to ball 'a' and ball 'b' by the wall along 'X' direction is :

JEE Main 2021 (Online) 25th July Morning Shift Physics - Center of Mass and Collision Question 46 English

Multiple Choice Options

  • A 1:01
  • B 2\sqrt 2 : 1
  • C 2:01
  • D 1 : 2\sqrt 2

Step-by-Step Verified Solution

Impulse = change in momentum

Ball (a) ∣Δp→∣\left| {\overrightarrow {\Delta p} } \right| = 2mu = J1

Ball (b) ∣Δp→∣\left| {\overrightarrow {\Delta p} } \right| = 2mu cos45 ∘^\circ = J2

J1J2=1cos⁡45∘=2{{{J_1}} \over {{J_2}}} = {1 \over {\cos 45^\circ }} = \sqrt 2

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