Both the nucleus and the atom of some element are in their respective first excited states. They get de-excited by emitting photons of wavelengths λ N , λ A respectively. The ratio λ N λ A is closest to:

Step-by-step solution

λ N λ a =   E a E N , where E a   a n d   E N are energies of photons from atom and nucleus respectively. E N is of the order of MeV and E a in few eV . So, λ N λ a = 10 - 6 .