What did Rutherford scattering show about the atom?

What is the charge of an alpha particle?

Why were large-angle alpha deflections surprising in a diffuse positive-charge model?

An atom has radius about \(10^{-10}\,\mathrm m\) and a nucleus radius about \(10^{-15}\,\mathrm m\). Find the ratio of radii.

State the Coulomb potential energy between an alpha particle and a nucleus of charge \(+Ze\).

In a head-on alpha approach, why can the initial kinetic energy be set equal to electric potential energy at closest approach?

Derive the closest-approach distance for a head-on alpha particle with kinetic energy \(K\).

Why do most alpha particles pass through a thin metal foil with little deflection?

An alpha particle has kinetic energy \(5.0\,\mathrm{MeV}\). Convert this energy to joules.

Estimate the closest approach to gold \((Z=79)\) for a head-on \(5.0\,\mathrm{MeV}\) alpha particle.

Explain why increasing alpha-particle kinetic energy decreases the distance of closest approach.

Why does a rare backward alpha scattering event imply a massive target centre?

Compare the roles of electrons and the nucleus in the nuclear atom model.

If the foil is made thicker, what happens to the chance of alpha scattering, and why?

Why does Rutherford scattering not by itself explain atomic stability?

Derive how closest approach depends on nuclear charge number \(Z\) for fixed alpha kinetic energy.

Use Rutherford scattering to argue against the plum-pudding model.

Why is the closest-approach calculation an upper bound on nuclear radius?

Explain why quantum ideas are needed after the nuclear atom is established.

A head-on closest-approach estimate gives \(r_{\min}=3.0\times10^{-14}\,\mathrm m\). What can and cannot be concluded?