Question

neucleus is positive are negative when positive then electron is around move ,where electron is negative,then why electron is not came in necleus ...in nucleus present proton and neutron ..

Answer 1

nucleus consists of protons which are positive charge. And whereas electrons have negative charge. They don't come inside the nucleus while revolving around the nucleus because they have fixed orbits in which they revolve. As one of the postulate of Bohr says.