Question

A mass of 2kg moving at 6m/s collide n stick to.mass of 4kg resting on smooth surface. Speed after colision is​

Answer 1

Answer:

Speed after collision = 2 m/s

Explanation:

Given that,

Initial Speed of mass 2kg = u₁ = 6 m/s

Initial Speed of mass 4kg = u₂ = 0 m/s (Body is at rest initially)

Final speed of both masses together = v = ?

By Conservation of linear momentum,

Total Inital Momentum = Total Final Momentum

m₁u₁ + m₂u₂ = Mv      

Here,

M = m₁ + m₂  (Both masses stick together after collision)

Therefore,

m₁u₁ + m₂u₂ = Mv

2*6 + 4*0 = (2 + 4)v

6v = 12

v = 12/6

v = 2 m/s

Therefore, speed after collision = 2 m/s