Which situations describe an elastic collision?
a. two glass marbles bounce off each other.
b. rodrick flops onto his sofa and sinks into the cushion.
c. a tossed water balloon flattens when it lands on the grass.
d. a bowling ball knocks over five pins.

Answer;

A. two glass marbles bounce off each other.

Explanation;

Elastic collisions are collisions in which both momentum and kinetic energy are conserved. The total system kinetic energy before the collision equals the total system kinetic energy after the collision. If total kinetic energy is not conserved, then the collision is referred to as an inelastic collision.

An elastic collision occurs when the two objects "bounce" apart when they collide. Two rubber balls are a good example. In an elastic collision, both momentum and kinetic energy are conserved. Almost no energy is lost to sound, heat, or deformation.

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