TC 9-64 _________________________________________________________________________
27. A sound wave that is reflected back toward the source is known as what type of sound?
28. What is the term for multiple reflections of sound waves?
29. A cavity that vibrates at its natural frequency produces a louder sound than at other
frequencies. What term is used to describe this phenomenon?
30. What do we call a disturbance that distracts or distorts the quality of sound?
31. What are three means of producing light?
32. What is the smallest unit of radiant energy?
33. What unit is used to measure the different wavelengths of light?
34. What are the three primary colors of light?
35. What are the three secondary colors of light?
36. White light falls upon a dull, rough, dark-brown object. Will the light primarily be reflected,
diffused, or absorbed by the object?
37. What color will be emitted by a dull, rough, black object when white light falls upon it?
38. A substance that transmits light but through which an object cannot be seen clearly is
known as what kind of substance?
39. At what speed does light travel?
40. A light wave enters a sheet of glass at a perfect right angle to the surface. Is the majority of
the wave reflected, refracted, transmitted, or absorbed?
41. When light strikes a piece of white paper, the light is reflected in all directions. What do we
call this scattering of light?
42. What three examples of electromagnetic energy are mentioned in the text?
43. What is the main difference between the bulk of the electromagnetic spectrum and the
44. What are the two components (fields) that make up the electromagnetic wave?
45. What do we call a conductor (or set of conductors) that radiates electromagnetic energy into
46. What do we call the field that is created between two rods when a voltage is applied to them?
47. When current flows through a conductor, a field is created around the conductor. What do we
call this field?
48. An induction field is created around a conductor when current flows through it. What do we
call the field that detaches itself from the conductor and travels through space?