Concept:In a perfectly elastic, 1-dimensional collision between two perfectly identical masses, both momentum and kinetic energy are conserved.
Solution:- When we solve the simultaneous conservation equations (Momentum: \( mv_1 = mv_1' + mv_2' \) and KE: \( \frac{1}{2}mv_1^2 = \frac{1}{2}mv_1'^2 + \frac{1}{2}mv_2'^2 \)), a unique mathematical symmetry emerges.
- The solution mandates that the objects perfectly swap their initial velocity states.
- The moving body stops completely, transferring 100% of its momentum to the second body, which shoots forward with the original velocity.
- Thus, their velocities are exactly interchanged.
Why other options are incorrect:- Option A violates the prompt which states it is elastic.
- Option C means the moving body passed through the stationary one like a ghost.
- Option D violates conservation of momentum.
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