Does light consist of waves or particles?

What did we learn from the photoelectric effect?

What is a photon and how do you determine its energy?

Atomic electrons have only specific allowed energy states. Why?

If light has a dual nature, what about electrons? Are they particles or waves?

How is the wavelength of an electron determined?

If atoms occupy only certain allowed levels, how do they get from one allowed level to another?

Why do atoms emit or absorb only certain specific colors of light?

Are all kinds of electromagnetic radiation dangerous to you? Which are most dangerous and why?

How can you tell that there is calcium in the atmosphere of the star Betelgeuse, which is about 310 light years away from the earth?

How do you determine the temperature of a hot object using the blackbody radiation curve?

How do you determine the temperature of a star?

If an ambulance with a siren passes you, what do you observe about the pitch of the siren before and after it passes you?

What happens to the wavelength of a light source that is approaching you? receding from you?

How do you identify hydrogen in a star that is moving with respect to you?

Why does the uncertainty principle imply that it would take a lot of energy to confine an electron in a very small volume like a nucleus?

What steps are necessary to get the intense light of a laser?

What is the source of the energy which makes stars shine?