Question: An electric discharge causes atomic hydrogen to emit photons with energies of 1.89, 2.55, and 2.86eV. In an experiment these are passed through a 1mm wide slit and then through a diffraction grating that has 5000 rulings per centimeter. The photons then go on and strike a screen 1m away.
a. What are the wavelengths of these photons?
b. Describe what appears on the screen and where. Be quantitative. Also give colors and tell how you know them.
c. Explain why these results suggest that light is a wave?