Question Detail
Question
A 2 kg object moving at 3 m/s collides head-on and sticks to a 4 kg object initially at rest. The speed of the combined object after the collision is:
Correct Answer
Option A is the correct answer.
Detailed Explanation
For a perfectly inelastic collision, momentum is conserved: m1v1i + m2v2i = (m1+m2)vf. Substituting: (2 kg * 3 m/s) + (4 kg * 0) = (2+4) kg * vf => 6 = 6vf => vf = 1 m/s.
Hint
Use the formula for perfectly inelastic collisions: vf = (m1v1i + m2v2i) / (m1 + m2).