According to Bohr's theory E_n= Total energy, K_n= Kinetic energy, V_n= Potential energy, r_n= Radius of n th orbit

Step-by-step solution

According to Bohr's theory, Total energy is E_n=K_n+V_n Kinetic energy =K_n= 1 8 ₀ Z e^2 r Potential energy =V_n= 1 4 ₀ Z e^2 r E_n= 1 8 ₀ Z e^2 r - 1 4 ₀ Z e^2 r Radius of n th orbit (r_n )= n^2 h^2 ₀ m Z e^2 E_n=- m e^4 8 ₀^2 h^2 1 n^2 (A) V_n K_n = - 1 4 ₀ Z e^2 r 1 8 ₀ Z e^2 r =-2 Hence, (A) match with (R) . (B) E_n 1 n^2 or E_n 1 r_n Radius of n th orbit r_n E_n^x x=-1 Hence, (B) match with (Q). (C) Angular momentum = h 2 l(l+1) l =0,1,2, For the lower orbit n=1 l=0 and m=0 Hence, angular momentum of lowest or