Question

What is the Wavelength of energy emitted when electron fall from the third energy level to the second ? What type of electromagnetic radiation is it

Answer 1

If an electron falls from the 3-level to the 2-level, red light is seen. This is the origin of the red line in the hydrogen spectrum. From the frequency of the red light, its energy can be calculated. That energy must be exactly the same as the energy gap between the 3-level and the 2-level in the hydrogen atom.

red light= Infrared radiation

hope that helps :D