In Rutherford's α-particle scattering experiment, most α-particles passed through the foil with little or no deflection, but a very small fraction were deflected through very large angles. Which conclusion is most directly supported by the rare large-angle scattering?
Options

Question

In Rutherford's α-particle scattering experiment, most α-particles passed through the foil with little or no deflection, but a very small fraction were deflected through very large angles. Which conclusion is most directly supported by the rare large-angle scattering?

Options

G1 Physics · Accepted Answer

A large-angle deflection requires a very strong repulsive electric field acting over a very small distance. Such strong deflection cannot be produced by a diffuse positive charge spread throughout the whole atom. It indicates that the positive charge is concentrated in a tiny central region. Because α-particles are massive and occasionally reverse direction, the central region must also contain nearly all of the atomic mass. Correct option: B.