5 1-38.   Which of the following units of measurement is/are used to measure very short wavelengths of light? 1.   Angstrom ( 2.   Millimicron 3.   Both 1 and 2 above 4.   Millimeter 1-39.   What are the primary colors of light? 1.   Red, blue, and yellow 2.   Red, blue, and green 3.   Red, violet, and indigo 4.   Blue, green, and violet 1-40.   What are the secondary colors of light? 1.   Orange, yellow, and blue-green 2.   Magenta, yellow, and cyan 3.   Purple, yellow, and black 4.   Red, white, and blue 1-41.   What causes sunlight to separate into different wavelengths and display a rainbow of colors when passed through a prism? 1.   Refraction 2.   Reflection 3.   Dispersion 4.   Diffraction 1-42.   The sun, gas flames, and electric light filaments are visible because they are 1.   opaque 2.   transparent 3.   nonluminous 4.   self-luminous 1-43.   Substances that transmit almost all of the light waves falling upon them possess which of the following properties? 1.   Opaqueness 2.   Transparence 3.   Translucence 4.   Self-lumination 1-44.   Some substances are able to transmit light waves but objects cannot be seen through them. Which of the following properties does this statement describe? 1.   Opaqueness 2.   Transparence 3.   Translucence 4.   Self-lumination 1-45.   The speed of light depends on the medium through which light travels. For which of the following reasons does light travel through empty space faster than through an object such as glass? 1.   Space is less dense than glass 2.   Space is more dense than glass 3.   Glass reflects the light back to the source 4.   Glass refracts the light, causing the light to travel in all directions 1-46.   If a light wave strikes a sheet of glass at a perpendicular angle, what is the effect, if any, on the light wave? 1.   The wave is completely absorbed 2.   The wave is reflected back toward the source 3.   The wave is refracted as it passes through the glass 4.   The wave is unchanged and continues in a straight line 1-47.   The amount of absorption of the light that strikes an object is determined by the object’s 1.   color 2.   purity 3.   density 4.   complexity