Question

A 0.86kg grenade is tossed on the ground with a velocity of 6 m/s West. If the grenade explodes into 2 pieces,
one that has a mass of 32kg and travels East at 10 m/s.
(A) What is the mass of the second piece
(B) What is the velocity of the second piece?

Answer 1

Answer:

(A) 0.54 kg

(B) 15.5 m/s west

Explanation:

Mass is conserved.

M = m₁ + m₂

0.86 kg = 0.32 kg + m₂

m₂ = 0.54 kg

Momentum is conserved (take east to be positive).

Mv = m₁v₁ + m₂v₂

(0.86 kg)(-6 m/s) = (0.32 kg)(10 m/s) + (0.54 kg) v₂

v₂ = -15.5 m/s