Answer:
V = 5.83 m/s
Step-by-step explanation:
Given that,
Mass of a ball of a clay, m = 2 kg
Initial speed of the clay, u = 35 m/s
Mass of a box, m' = 10 kg
Initially, the box was at rest, u' = 0
We need to find the velocity of the box after the collision. Let V be the common speed. Using the conservation of momentum to find it.

So, the velocity of the box after the collision is equal to 5.83 m/s.