QJEEM23Ph36af: JEE Main 2023 Physics - Class 11 JEEM23Ph36af Solution: A particle of mass m moving with velocity v collides with a…

When two particles collide, the total momentum before the collision is equal to the total momentum after the collision, according to the law of conservation of momentum. Therefore, we can write:

$mv = (m+2m) v_f$

where $v_f$ is the final velocity of the combined particles.

Simplifying the above equation, we get:

$v_f = \frac{mv}{3m} = \frac{v}{3}$

So, the correct option is $\frac{v}{3}$ .