1. All objects radiate energy, in much the same way as an ideal blackbody. So why is it difficult to see objects in a dark room? Explain.
2. Explain why the existence of a cutoff frequency in the photoelectric effect supports a particle model of light, rather than a wave model.
3. In a Compton scattering experiment, x-ray photons strike free electrons and are scattered in different directions as a result. Compare the energy, wavelength, and momentum of the scattered x-ray photons to those of the incident x-ray photons.