- Frequency represents the property of waves.
- Waves are having cycles, the number of cycles per unit time period is called frequency (f).
- Frequency is inversely proportional to the wavelength.
f = cycles / time (T).
Types of frequency:
1.Angular frequency: It is defined as rate of change of angular displacement or rate of change of phase. It is measured in radians per second.
y(t) = sin(2*pi*ft).
2.Spatial frequency: It is analogous to frequency but time is replaced by one or more spacial displacement axes. It is measured in radians per meter.
y(t)= sin (wt + kx).
In Propagation:
Light: Visible light is an electromagnetic wave, consists of oscillating electric and magnetic fields travelling through space.
Sound: Sound is a mechanical wave in air or any other medium. Frequency is the property that determines pitch.
Line Current: The alternating current travels through the conductor in the form of sine wave.
In India, Australia, Africa, Russia the frequency of the alternating current is 50 Hz. Where as in North and South America it is 60 Hz.
Notes:
