9. Quantum Mechanics

What is the frequency of a helium-neon laser light with a wavelength of 632.8 nm? The speed of light is 3.00 x 10^8 m/s.

What is the wavelength of light emitted (in nm) when the electron in a hydrogen atom moves from n=4 to n=2?

Consider the two waves shown here (figure 1), which we will consider to represent two electromagnetic radiations.