Question

How big is a neutron relative to a proton?

Answer 1

A neutron is about three times the size of a proton.

Explanation:

The relative atomic mass of a proton is 1 and is the same for the neutron.

Therefore, a logical assumption would be that they are the same size — and that is a good approximation.

According to recent theories, a proton is a thin positive ring with radius `2 × 10^(-16) color(white)(l)"m"`.

A neutron is a thin positive ring with radius `2 × 10^(-16)color(white)(l) "m"` inside a thin negative ring with radius `6 × 10^(-16)color(white)(l) "m"`.

Thus, a neutron is 3 times the size of a proton.