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QJEEM21Ph1423: JEE Main 2021 Physics - Class 11 JEEM21Ph1423 Solution: Two identical blocks A and B each of mass m resting on the…

Two identical blocks A and B each of mass m resting on the smooth horizontal floor are connected by a light spring of natural length L and spring constant K. A third block C of mass m moving with a speed v along the line joining A and B collides with A. The maximum compression in the spring is

JEE Main 2021 (Online) 17th March Evening Shift Physics - Center of Mass and Collision Question 56 English

Multiple Choice Options

  • A mvK
  • B m2K
  • C mv2K
  • D vm2K

Step-by-Step Verified Solution

JEE Main 2021 (Online) 17th March Evening Shift Physics - Center of Mass and Collision Question 56 English Explanation 1

From conservation of momentum

mv = mv1 + mv1

V1=V2

JEE Main 2021 (Online) 17th March Evening Shift Physics - Center of Mass and Collision Question 56 English Explanation 2

And from energy conservation

12mv2=(12×m(V2)2)×2+12Kx2

mv22−mv24=12kx2

mv24=12kx2

Then the maximum compression in the spring is

x=mv22K

⇒ x = vm2K

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