Energy liberated in the de-excitation of hydrogen atom from the third level falls on a photo-cathode. Later when the same hoto-cathode is expoced to a spectrum of some unknown - like gas, excited to the second energy level , it is found that the de Broglie wavelength of the fastest photoelectrons now ejected has decreased by a factor of `3`. For this new gas, difference of energies of the second Lyman line and the first balmer line is found to be `3` times the ionization potential of the hydrogen atom. Select the correct statement (s):

An electron is excited to fourth energy level in an atom. It will

Radiation from hydrogen gas excited to first excited state is used for illuminating certain photoelectric plate . When the radiation from same unknown hydrogen-like gas excited to the same level is used to expose the same plate , it is found that the de Broglie wavelength of the fastest photoelectron has decreased 2.3 time gt It is given that the energy corresponding to the longest wavelength of the Lyman series of the known gas is 3 times the ionization energy of the hydrogen gas (13.6 eV) . Find the work function of photoelectric plate in eV . [Take (2.3)^(2) = 5.25]

The ratio of the energies of the hydrogen atom in its first to second excited state is

An electron, in a hydrogen like atom , is in excited state. It has a total energy of -3.4 eV, find the de-Broglie wavelength of the electron.

The ratio of the binding energies of the hydrogen atom in the first and the second excited states is

When an electron of hydrogen like atom jumps from a higher energy level to a lower energy level.