Question

An early model for an atom considered it to have a positively charged point Nucleus of charge Ze, surrounded by a uniform density of negative charge up to radius R.the atom as a whole is neutral.for this model what is the electric field at a distance r from the nucleus?

Answer 1

1. The model actually tries to prove that the atom is electrically neutral.
2. According to the Thomson model of the atom, the Electric field in an atom is experienced only up to the distance, which is less than the atomic radius.

Now, electric field at a distance 'r ' from the nucleus is

$E=k\frac{Ze}{r^2}$

For $r\ge R\left(Atomicradius\right)$

E=0