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.

Which of the following transitions requires the absorption of the most energetic photon?

What must be the velocity, in meters per second, of a beam of electrons if they are to display a de Broglie wavelength of 880 nm?