Electric current is basically two types, Alternating Current denoted as AC and Direct current DC. One of the main parameter of AC is the frequencies. The variation of current or voltage from zero, to a maximum positive point then again it come back to the zero and move to maximum negative point, and back to zero, is termed as “cycle” .
The number of cycle traversed by current or voltage in one second is known as its frequency. In other words number of cycles repeated in one second is called cycle per second or frequency.
Frequency is measured as hertz. If an ac cycle is completed in one second that frequency is called one hertz.
1000 Hz = 1KHZ (KiloHertz)
1000KHZ = 1MHZ (MegaHertz)
1000, 000 =1 GHZ (GigaHertz)
Frequency’s are classified as below as some special properties exhibited by them.
10 Hz - 30 Hz Very Low Frequencies (VLF)
30Hz – 300 Hz Low Frequencies (LF)
300 Hz -3 MHZ Medium Frequencies (MF)
3 MHZ -30 MHZ High Frequencies (HF)
30 MHZ - 300 MHZ Very High Frequency (VHF)
300 MHZ – 3000 MHZ Ultra High Frequency (UHF)
3000 MHZ – 30,000 MHZ Super High Frequency (SHF)
Electricity is travel at the speed of light, depends on the conductor there is some variations.
That means velocity of Ac 3 x 108 so the distance travelled by an alternating wave is called Wave length ( it is denoted by “ λ” Lamda).
The Wave Length λ = (Speed of light / Frequency) that is (3x108/F)