Chapter 24 Physics A First Course Light and Optics Light and Optics The Physical Nature of Light 24.1 The Electromagnetic Spectrum 24.2 Interference, Diffraction, and Polarization 24.3 Photons 24A Investigation: Optics Key Question: How is the color of light related to its wavelength? *Students read text section 24.1 AFTER Investigation 24A 24A Investigation Topics Use a diffraction grating to observe the spectrum of different light sources. Find the wavelengths of different colors of light using a spectrometer. Explain why light is a wave. Chapter 24.1 Objectives and Vocabulary Learn the relationship among the frequency. Learn how the speed of light changes in different materials. Identify the different kinds of electromagnetic waves. electromagnetic wave electromagnetic spectrum radio wave microwave infrared light visible light ultraviolet light X rays gamma rays Wavelength and Frequency of Visible Light Speed of Light c = f wavelength (m) frequency (Hz) speed of light 3 x 10 8 m/sec Chapter 24.2 Objectives and Vocabulary Recognize an interference pattern and how it is created. Understand the difference between polarized and unpolarized light. Learn about the applications of polarization. diffraction grating diffraction pattern polarizer Thin slits and diffraction 24B Investigation: Waves and Photons Key Question: How do we know light has both wave-like and particle-like qualities? *Students read text section 24.3 AFTER Investigation 24B 24B Investigation Topics Demonstrate the polarization of transverse waves. Observe the polarization of light. Explain why sunglasses work. Discuss the wave-like and particle-like behavior of light. Chapter 24.3 Objectives and Vocabulary Define the term photon. Explain how energy is related to the color of light. Learn that one photon affects one electron at a time. photoluminescence Absorbing and Emitting Light White paper absorbs and then emits photons of all colors of light. Black ink absorbs the photons of all colors and emits none.