Question

An excited h like species when bombarded by photons of wavelength

Answer 1

Answer:  1/lemda = R( 1/n1^2 - 1/n2^2)

Explanation:

According to Bohr when an atom makes a transition from higher energy level to a lower ta a lower energy level it emits a photon with energy equal to the energy difference between the initial and final levels. If E1 is the initial energy of the atom before such a transition E1 is its final energy after the transition ,and the photon's energy is hf = hc/lemda , then conservation of energy gives

hf = hc/ lemda = E1 - E2                           (energy of emitted photon)