Mass of one of the objects, m₁ = 1.5 kg
Mass of the other object, m₂ = 1.5 kg
Velocity of m1 before collision, v₁ = 2.5 m/s
Velocity of m₂, moving in opposite direction before collision, v₂ = -2.5 m/s
(Negative sign arises because mass m₂ is moving in an opposite direction)
After collision, the two objects stick together.
Total mass of the combined object = m₁ + m₂
Velocity of the combined object = v
According to the law of conservation of momentum:
Total momentum before collision = Total momentum after collision
m₁ + v₁ + m₂ v₂= (m₁ + m₂) v
1.5(2.5) + 1.5 (-2.5) = (1.5 + 1.5) v
3.75 – 3.75 = 3 v
v = 0
Hence, the velocity of the combined object after collision is 0 m/s.

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