Question

In an inelastic collision, two objects collide with each other and come to a rest. The first object’s initial momentum was 30kg⋅m/s . If the second object’s mass is 40kg , what was its initial momentum?

a) −30kg⋅m/s

b) 0kg⋅m/s

c) 30kg⋅m/s

d) 40kg⋅m/s

Answer 1

Since in inelastic collision too the momentum is conserved,

so, m₁ x v₁ + m₂ x v₂ = (m₁+m₂) x 0   (as after collision both objects come to rest)

m₁ x v₁ = 30 kg.m/s (given)

m₂ = 40 kg (given)

v₂ = -30/40

so its initial momentum = m₂ x v₂ = 40 x (-30/40) = -30 kg.m/s