Chapter II - Waves and Particles

2.1) Light of 300 nm wavelength strikes a metal plate and photoelectrons are produced moving as fast as 0.002 c. (a) What is the work function of the metal? (b) What is the threshold wavelength for this metal?

2.6) To expose photographic film, photons of light dissociate silver bromide (AgBr) molecules, which requires an energy of 1.2 eV. What limit does this impose on the wavelengths that may be recorded by photographic film?

2.10) A sodium vapor lamp emits 10 W of light energy. Its wavelength is 589 nm and it spreads in all directions. How many photons pass through your pupil, diameter 4 mm, in 1 s if you stand 10 m from the light?

2.14) A typical ionization energy - the energy needed to remove an electron - for the elements is 10 eV. Explain why the energy binding the electron to its atom can be ignored in Compton scattering involving an x-ray photon whose wavelength is about a tenth of a nanometer.

2.17) A 0.057 nm x-ray photon "bounces off" an initially stationary electron and scatters with a wavelength of 0.061 nm. Find the directions of scatter of (a) the photon, and (b) the electron.

2.23) Show that the angles of scatter of the photon and electron in the Compton effect are related by the following formula:

2.25) Pair annihilation. A stationary muon annihilates with a stationary antimuon (same mass, 1.88×10^-28 kg, but opposite charge). The two disappear, replaced by electromagnetic radiation. (a) Why is it not possible for a single photon to result? (b) Suppose two photons result. Describe their possible directions of motion and wavelengths.

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