Question

An object a of mass 2 kg is moving with a velocity of 3 m/s and collides head-on with an object b of mass 1 kg moving in opposite direction with a velocity of 4 m/s. After collision, both objects combine so that they move with a common velocity equal to

Answer 1

Given,

m₁= 2 kg

m₂= 1 kg

u₁= 3 m/s

u₂ = -4 m/s(Velocity is in opposite direction)

According to law of conservation of momentum,

m₁u₁+m₂u₂ =m₁v₁ + m₂v₂

After collision, they move with same common velocity

m₁u₁ +m₂u₂ = (m₁ + m₂)v

(2 X 3) + (1 X (-4)) = (2 + 1)v

6-4= 3v

2=3v

v=2/3

v= 0.6666 m/s