Infrared waves appear as heat when absorbed by objects. Practical Which diagram best represents wave reflection? 84. Which arrow best represents the path that a applications of the infrared portion of the electromagnetic spectrum include heat lamps used in physical therapy and infrared photography. monochromatic ray of light (f - 5.09 x 10)4 Hz) Barrier travels as it passes through air, corn oil, glycerol, Visible light is approximately one percent of the electromagnetic spectrum, and back into air? It is produced by the rearrangement of electrons in atoms and molecules. The wavelengths that the human eye can detect are in the range of Air Air approximately 400 to 700 nanometers. Corn oil Com oil Ultraviolet light is the part of sunlight that causes sunburns. The ozone Glycerol Glycerol layer of the atmosphere filters practically all of the high frequency Air Air components of ultraviolet radiation from the Sun, but the inner atmosphere readily transmits the remaining lower frequency ultraviolet (1) (3) radiation. Some commercial skin lotions are designed to absorb ultraviolet Air Air rays to prevent them from affecting the skin. Corn oil Corn oil X rays are used as diagnostic tools by physicians. Living tissues and Glycerol Glycerol organisms can be destroyed by x rays, so precautions should be taken to Air Air avoid overexposure. (2) (4) Gamma rays are emitted by radioactive nuclei. This electromagnetic radiation is harmful to living tissues. 85. What happens to the speed, wavelength, and frequency of light when it passes from water into flint glass? ReviewYestions (1) Its speed decreases, its wavelength becomes shorter, and its frequency remains the same. 2) Its speed decreases, its wavelength becomes 72. How long does it take light to travel a distance 77. The diagram below represents a light ray being reflected from a plane mirror. The angle shorter, and its frequency increases. of 100. meters? 1) 3.00 X 1010 s between the incident and reflected ray is 70. (3) Its speed increases, its wavelength becomes (3) 3.33 x 10 7 s longer, and its frequency remains the same. (2) 3.00 X 10's (4) 3.33 x 10's 80. When a ray of light strikes a mirror 4) Its speed increases, its wavelength becomes 73. Calculate the wavelength in a vacuum of a light perpendicular to its surface, what is the longer, and its frequency decreases. wave having a frequency of 5.3 x 10" hertz. Incident ray angle of reflection? 86. Which ray diagram best represents the Express the wavelength in nanometers. Y Reflected ray 81. A ray of light passes from air into glass at an phenomenon of refraction? 74. What is the frequency of a light wave having a angle of incidence of 0'. Which statement best wavelength of 5.00 x 10 7 meter in a vacuum? 70. describes the speed and direction of the light (1) 6.00 x 10 14 Hz (3) 6.00 X 1015 Hz ray as it passes into the glass? Plane mirror Water Water Wate (2) 6.00 x 1014 Hz (4) 6.00 X 1016 Hz (1) Only speed changes. Water 75. Which form(s) of energy can be transmitted What is the angle of incidence for this ray? (2) Only direction changes. through a vacuum? (1) 20." (2) 350 (3) 550 (4) 70. (3) Both speed and direction change. (1) (2) (3) (4) (1) light, only (4) Neither speed nor direction changes. (2) sound, only 78. In the diagram below, ray R of monochromatic 82. As a wave enters a new medium, there may be a 87. In the diagram below, ray AB is incident on (3) both light and sound yellow light is incident upon a glass surface at change in the wave's surface XY at point B. (4) neither light nor sound an angle 0. (1) frequency (3) period 76. A ray is reflected from a surface, as shown in the (2) speed (4) phase diagram that follows. 83. The speed of a ray of light traveling through a Medium 2 Normal substance having an absolute index of refraction Medium 1 / B ncident Reflected Glass of 1.1 is ray ray (1) 1.1 X 10 s (3) 3.0 X 10 s Diamond (2) 2.7 X 10 s (4) 3.3 X 10 s If medium 2 has a lower index of refraction than medium 1, through which point will the ray most likely pass? Which letter represents the angle of incidence? Which resulting ray is not possible? 168 Topic 5: Waves Topic 5: Waves 169