Impact and collisions — elastic impact and relative velocity For a perfectly elastic impact, relate the relative velocity after impact to the relative velocity before impact. Choose the correct statement.
Mechanical Engineering
Engineering Mechanics
Difficulty: Easy
Choose an option
Answer
Correct Answer: equal and opposite to
Explanation
ConceptCoefficient of restitution, e = 1 for a perfectly elastic impact.
Key relationRelative velocity of separation = e × Relative velocity of approachFor e = 1, magnitude after impact equals magnitude before impact, but the direction reverses.
Final Answerequal and opposite to