Answer: Ernest Rutherford, a New Zealand-born physicist, outlined the structure of an atom in 1911. The atom is defined by Rutherford's atomic theory as a tiny, dense, positively charged core called a nucleus that is encircled by negative charges called electrons.
Explanation: Rutherford's atomic model makes the following assumptions:
The positive charge and the major portion of an atom's mass are concentrated in an extremely small volume. He alluded to this region of the atom as the nucleus.
As per Rutherford's model, negatively charged electrons encompass an atom's nucleus. He also alleged that the electrons surrounding the nucleus travel in circular paths at high velocities. These circular paths were designated orbits by him.
A strong electrostatic attraction force retains electrons, which are negatively charged, and the nucleus, which is a densely concentrated mass of positively charged particles, together.