Photons of frequencies equal to the frequencies of H_ and H_ lines of hydrogen incident on a photosensitive plate, whose threshold frequency is equal to the frequency of H_ line of hydrogen. The ratio of the maximum kinetic energies of the emitted electrons is

Step-by-step solution

Energy of photons of aligned H _ line = E(3 & 2) & =13.6 ( 1 4 - 1 9 )= 13.6 5 36 =1.89 eV aligned Energy of photons of H _ line = E(4 2) =13.6 ( 1 4 - 1 16 )= 12 13.6 64 =2.55 eV Energy of photons of H _ line = E( 2) = 13.6 4 =3.4 eV Ratio of kinetic energy of emitted photons = 255-1.89 3.4-1.89 = 0.66 1.51 0.7 1.6 7 16