1.physical geography examines the culture, political systems, social systems, economic systems, and characteristics of various peoples—why they eat certain foods, practice a chosen religion, or why they select a particular mode of transportation. a. true b. false

Which theory was contradicted by experiments with the photoelectric effect? light spreads out after it passes through a small opening. as soon as light strikes metal, electrons will be ejected. visible light, regardless of color, will cause the ejection of electrons when striking metal. the kinetic energy of ejected electrons depends on the frequency of light that strikes the metal.