Question

What is the wavelength of light emitted when the electron in hydrogen atom undergoes transition from an energy level with n is equal to 42 and energy level n is equal to 2?

Answer 1

Answer:

Rh=1.0977×10^7 per metre

1/wavelength=Rh(1/2^2. - 1/42^2)

wavelength= 441/110. ×Rh

= 4.009/Rh.. per metre

Answer 2

Answer:

Electrons are emitted with zero velocity from a metal surface when it is exposed to radiation of wavelength 6800 Å.