If an electron undergoes transition from 4th to 2nd orbit, then the color of radiations produced will be:
Correct answer: B. Blue-green
- A. Violet
- B. Blue-green
- C. Ultraviolet
- D. Infrared
Explanation
Transition is to 2nd orbit which means we have to use the formula for Balmer series which is: 1/λ = RH (1/22 - 1/n2)For 4th orbit: 1/λ = RH (1/22 - 1/42)So, wavelength comes out to be: λ = 485.99nmWe know that this is the wavelength of blue green light. Therefore, Blue-green radiations will be emitted. Here is the complete spectrum:
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About Dawn of Modern Physics
Classical physics cannot explain blackbody radiation and related observations, leading to Planck’s quantum theory, in which energy is emitted or absorbed in discrete packets. Photons provide the particle model of light, with energy and momentum linked to frequency and wavelength, including the photoelectric effect and its threshold frequency.
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