Question: Write few characteristics which describe a wave?
Characteristics of waves
The parameters which describe the wave in terms of its production, speed, and energy etc. are called characteristics of waves. Few of the wave characteristics are given below.
(1) Wavelength, λ
The shortest distance between any two points where the wave pattern repeats itself is called wavelength. Its symbol is λ and measuring unit is meter.
As a wave is a cyclic phenomenon, it continuously repeats itself. This means that after a change of one wavelength distance, the wave starts to repeat itself. For convenience, we can say that in case of transverse waves, it is the shortest distance between two consecutive crests or two consecutive troughs, whereas in longitudinal waves, it is the distance between two consecutive compressions or rarefactions.
(2) Amplitude x0
It is the displacement between the mean position and extreme position of the vibrating medium particles. Its symbol is A or xo and measured in meters.
(3) Wave cycle
When the wave passes through a given point, the point undergoes a cyclic motion. The point is first displaced in one direction and then in the other. Finally, it comes to its equilibrium position. This whole journey is called one wave cycle. It is usually represented by number N.
(4) Frequency, f
Frequency of a wave is defined as the number of cycles (N) passing through a point in one second. Its unit hertz (Hz) equal to N s-1. Mathematically, .
f = N/t
(5) Time period, T
Time period is the time required to complete one cycle. It is denoted by T and its unit is second (s).
(6) Wave speed
The distance traveled by a wave in one second is called wave speed. It is denoted by v and its unit is ms-1. Mathematically,
v = distance/time = ΔS/Δt