4) What was Alhazen’s greatest contribution to science? 5) What is the name of the only particle that can travel at the speed of light?

7) What did William Herschel’s experiment with light and heat prove?
8) Why are organ pipes in the Abbey different lengths?
9) What is the difference between light and sound waves as they travel?
10) Which color has the lowest amount of energy, and why?
11) Why are there dark bands in the spectra Joseph Fraunhofer saw?
12) What did Joseph Fraunhofer discover about the elements that make up the universe? only his tent, a piece of wood, and a ruler?