What are characteristics of electromagnetic waves ?

Explanation

Electromagnetic radiation : When electrically charged particle is accelerated alternating electric and magnetic fields are produced and transmitted. These fields are transmitted in the form of waves called electromagnetic waves or electromagnetic radiation.
Important Characteristics of a wave:
1) These are produced by oscillating charged particles in a body.
2) These radiations can pass through vacuum also. So medium for transmission is not required.
3) Velocity (c): It is defined as the linear distance travelled by the wave. in one second, Units : `cmsec^(-1)` (or) `msee^(-1)`
All kinds of electromagnetic waves have the same velocity.
`(3xx10^(8)msec^(-1) or 3xx10^(10)cmsec^(-1))`
4) Wavelength `(lamda)` It is defined as the distance between any two successive crests or troughs of wavez.
Units : A,m,cm, nm or pm `1Å=10^(-10)m`
`1nm=10^(-9)m=10^(-7)cm`
`1"pm"=10^(-12)m`.
5) Frequency (v): It is defined as the number of waves passing through a point in one second.
Units : Hertz (Hz), cycles `sec^(-1)` or `sec^(-1)`
`v=(c)/(lamda)`

6) Wave number `(barv)`: It is defined as the number of waves present in one unit length. It is equal to the reciprocal of the wavelength.
`barv=(1)/(lamda)=(v)/(c)`
Relation between wavelength and frequency:
`c=vxxlamdaimpliesv=(c)/(lamda)`
7) Amplitude (A) is the height of the crest (or) depth of through of a wave. It determines intensity (or) brightness of the wave.