Two objects of masses 100 g and 200 g are moving along the same line and direction with velocities of 2 m s–1 and 1 m s–1, respectively. They collide and after the collision, the first object moves at a velocity of 1.67 ms–1. Determine the velocity of the second object.

Mass of one of the objects (m1) = 100 g = 0.1 kg

Mass of the other object (m2) = 200 g = 0.2 kg

Velocity of m1 before collision (v1) = 2 m/s

Velocity of m2 before collision (v2) = 1 m/s

Velocity of m1 after collision (v3) = 1.67 m/s

Velocity of m2 after collision= v4

According to the law of conservation of momentum:

Total momentum before collision = Total momentum after collision

Therefore, m1v1 + m2v2 = m1v3 + m2v4

On substituting the known and given values we get

2(0.1) + 1(0.2) = 1.67(0.1) + v4 × (0.2)

0.4 = 0.167 + 0.2 × v4

v4= 1.165 m/s

Hence, the velocity of the second object becomes 1.165 m/s after the collision.