Summarize how the sign of the charge affects the direction of the force (attraction or repulsion) in two complete sentences or more.

Unlike charges attract Like charges repel.

A study of structure of atom reveals that there exist fundamental particle namely proton and neutrons in it.

Protons and neutrons lie in the central part of atom.

There is a force present in the nucleus of an atom in orbit and electrons that revolve round the nucleus. These outermost orbitals and the electrons present in them are called valence electrons.