PHYSICS · Single correct · CBSE · Physics · Work, Energy and Power · Work, Energy and Power
Problem
Two identical billiard balls, each of mass 0.16kg, move on a level, nearly frictionless table. Ball A travels due east at 4.0m/s and collides with ball B, which is initially at rest. After the collision, ball A moves at 2.5m/s at 45∘ north of east, and ball B moves at 3.0m/s at 45∘ south of east.
Based on these data, which of the following best describes the type of collision?
(a) Elastic, because the total momentum is conserved in both the x and y directions.
(b) Inelastic, because the total kinetic energy decreases by about 5%.
(c) Perfectly inelastic, because any loss of kinetic energy means the collision is perfectly inelastic.
(d) Elastic, because the 5% change in kinetic energy is within typical experimental uncertainty.