A hypothetcal, hydrogen like atom consists of a nucleus of mass `m_(1)` and charge `(+Ze)` and a nu-meson of mass `m_(2)` and charge (-e). Using Bohr's theory, derive an expression for distance between nucleus and mu-meson for principal quantum number n and derive a relation for energy also. Hence obtain expression for reduced mass.

Answer

`[r =(epsilon_(0)n^(2)h^(2)(m_(1)+m_(2)))/(pim_(1)m_(2)Ze^(2)),E =- (1)/(8)(m_(1)m_(2)Z^(2)e^(4))/((m_(1)+m_(2))epsilon_(0)^(2)n^(2)h^(2)),m_(0)=(m_(1)m_(2))/(m_(1)+m_(2))]`