(d) According to Bohr's model, the kinetic energy of moving electron in nth orbit is given as K=
Rhc
n2
⋅⋅⋅⋅⋅⋅⋅(i) where, R= Rydberg constant, h= Planck's constant and c= speed of light. Similarly, potential energy of electron moving in nth orbit, P=−2
Rhc
n2
⋅⋅⋅⋅⋅⋅⋅(ii) From Eqs. (i) and (ii), we have P=−2K Total energy of electron moving in nth orbit, E=K+P=K−2K E=−K ⇒K=−E=−(−3.4eV)(givenE=−3.4eV) K = 3.4 eV From Eq. (iii), we have P=−2K=−2(3.4)=−6.8eV ∵P−K=−6.8−3.4=−10.2eV and K−P=3.4−(−6.8)=10.2eV