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sciencechapter 17
Question | Answer |
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Distance | The separation in time or space between two points or locations. A scalar quantity that represents the length of a path from one point to another. |
Interference | The effect produced by two or more waves passing simultaneously through a region. Patterns of constructive and destructive interference depend on the nature of the combining waves. |
period | The time required for the completion of a single vibration, or event, of a periodic phenomena, such as a periodic wave or an orbit. The second, s, is the standard unit for period of a wave. The period is the reciprocal of the frequency of a wave: |
formula for period | T = 1/f |
frequency | The number of vibrations occurring per unit of time. The frequency of a wave is inversely related to its period. The hertz , Hz, is the standard unit of frequency: 1 Hz = 1 cycle/second. |
formula for frequency | f = 1/T. |
periodic wave | A series of regular (evenly timed) disturbances in a medium. |
refraction | The change in direction of a wave that occurs when the wave passes at an angle through a boundary between two different media and across which there is a change in speed. |
longitudinal waves | The vibratory disturbance in a longitudinal wave is parallel to the direction of travel of the wave. For example, sound waves are longitudinal. |
amplitude | The maximum distance from the rest position in a wave. Amplitude is related to intensity. As the amplitude of a light wave increases, the light gets brighter. As the amplitude of a sound wave increases, the sound gets louder. |
reflected ray | When an incident ray strikes a surface, the light ray that is reflected from it is called the reflected ray. The angle of reflection is equal to the angle of incidence. |
destructive interference | the effect of when a wave crest meets a wve trough, the waves will combine to form a wave with a lower amplitude. maximum=180 degrees. |
angle of incidence | The angle at which an incident light ray or other wave strikes the surface of a medium, measured relative to a normal (perpendicular) to the surface. In the diagram below, the angle of incidence is θ. always equal to the angle of reflection! |
medium | An environment in which a reaction can occur, or a material though which a disturbance travels. For examples, sound waves travel through the air. |
constructive interference | the result of a wave crest meeting a crest, when the two waves combine to form a larger amplitude. Maximum constructive interference occurs at points where the phase difference is 0°. |
transverse wave | The vibratory disturbance of a transverse wave is perpendicular to the direction of travel of the wave. For example, light waves are transverse. |
displacement | A vector quantity that represents the length and direction of a straight line path from one point to another. The magnitude of displacement is distance. |
angle of reflection | The angle at which a light ray or other wave is reflected from the surface of medium, measured relative to a normal (perpendicular) to the surface. In the diagram below, the angle of reflection is θ. always equal to the angle of incidence! |
regular reflection | An effect produced by polished surfaces, usually resulting an image of the source. |
hertz | The standard unit of frequency: 1 hertz = 1 cycle/second. |
standing wave | Produced when two waves of the same frequency and amplitude travel in opposite directions in the same medium. A standing wave does not travel (hence its name); instead, it oscillates about an equilibrium position. |