This document contains a summary of several physics concepts related to wave-particle duality and quantum physics. It includes 3 sample problems worked out in detail that demonstrate: 1) using the Compton scattering equation to estimate the Compton wavelength from experimental data, 2) relating the number of photons emitted by a laser to its power and photon energy, and 3) calculating the energy of the most energetic electron in uranium using the particle in a box model. The worked problems provide insight into applying relevant equations and show the conceptual and mathematical steps.