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Two identical particles move towards each other with velocity 2v and v respectively. Velocity of centre of mass is

1. v
2. v/3
3. v/2
4. zero

Correct answer: v/2

Solution

The velocity of the center of mass is calculated using the formula v_cm = (m1*v1 + m2*v2) / (m1 + m2). Since the particles are identical, their masses are equal, and the center of mass velocity is the average of their velocities, which results in v/2.

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