What properties of the alpha particle and the gold nucleus in the original Rutherford experiment were responsible for the collisions being elastic collisions?

Short Answer

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The property that both the nuclei remained in their ground states

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01

Given information

The original Rutherford experiments.

02

The Rutherford experiment

In the gold-foil experiment, physicist Ernest Rutherford proved the nuclear theory of the atom. A few alpha particles were deflected when he fired a stream of particles against a sheet of gold foil. He concluded that a tiny, dense nucleus was causing the deflections.

03

Properties of alpha particle responsible for the elastic collision 

The original Rutherford experiment interpreted collisions between the alpha particle and the gold nucleus to be elastic since both nuclei stayed in their ground states. That is, the internal energies of the gold nucleus and alpha particle do not vary during the collision, and the overall energy of the gold nucleus and alpha particle system remains constant, resulting in an elastic collision.

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