Question

A periodic wave has a fixed pattern that is repeated. What is one completion of the wave pattern called?

Answer 1

A periodic wave is a wave which is a periodic function of space and time and its motion is repeated after each period .

One may consider an example of water wave which is produced due to any disturbance .It is a transverse wave which forms crests and troughs.The crests and troughs are repeated through out the medium. .Hence we may say that it is a series a crests and troughs.

The periodic wave is characterized by various parameters called amplitude ,wavelength and frequency etc.

AMPLITUDE: The amplitude of a wave is the maximum displacement of the wave .In case of water wave we may define it as the maximum displacement between resting position and crests or troughs.

TIME PERIOD: The time period of wave is defined as the time taken by the wave for one complete oscillation.We may say it as the time taken by a wave to travel a distance equal to its wavelength. Wavelength is the distance between two successive crests or troughs.

CYCLE: The wave is a  periodic motion of time and space .The periodic wave follows a specific pattern which is repeated in space or medium.In water wave we may take crest and trough.One crest and trough is called one cycle and time taken for one cycle is the time period.

FREQUENCY: The frequency of a  wave is defined as the number of cycles passing through a point in one second.It is the reciprocal of time period .

Mathematically frequency f = 1/T

PHASE: The phase of a wave is defined as the instantaneous  position of a point in the cycle of wave form.

Hence from above we get that one completion of the wave pattern is called cycle of the wave.

Hence the correct answer is d .

Answer 2

The correct answer is d. cycle. A concept somehow related to this is an oscillation; that is a repetitive variation. Often, one speaks of the number of oscillations or cycles and refers to the same thing.