Topic : Electro magnetics waves
The wave which have
oscillating electric and Magnetic fields which are mutually perpendicular to
each other and also perpendicular to the direction of propagation of wave is
called as Electromagnetic wave
The above picture Shows EM
wave travelling along X- axis. Which have oscillating electric field along y
axis and Oscillating magnetic field along Z-axis?
Source of EM waves:-
1. Accelerated charges radiate energy in the form of EM
waves. So it is source of EM waves
2. An oscillating charge produces an oscillating electric
field in turn which produces an oscillating magnetic field.
3. The oscillating electric and magnetic fields regenerate
each other and propagate through space as waves called EM waves.
4. An electric charge oscillating harmonically with frequency
produces EM waves of same frequency.
5. EM wave generated in LC
circuit
Nature of
electromagnetic wave:
Electromagnetic wave has
oscillating electric and magnetic fields which are mutually perpendicular to
each other and also perpendicular to the direction of propagation of wave
Electromagnetic wave travel along the direction of E X B
If EM wave is travelling along
positive direction along x-axis, the electric field is oscillating parallel to the
y-axis and that magnetic field is oscillating parallel to z-axis, then we can
write the electric and magnetic fields as sinusoidal functions of position ‘x’
and time t
Electric field at any instant
Along Y axis
Ey=Eo sin(kx-ωt))
Magnetic field at any instant Along Z axis
Bz=Bo sin(kx-ωt)
Where E0 and B0 are the Are Peak values or Amplitudes of electric and magnetic
fields
K is propagation constant or Wave number
k=2Π/λ
λ is wavelength of electromagnetic wave
ω is angular frequency ω=2πυ = 2π/T
υ is frequency of EM wave, T is time period
x is the Distance travelled by EM wave
For video lecture click below
Subscribe physics channel click below for class 11 and 12 CBSE,NEET
https://www.youtube.com/c/srinivasphysicsclasses
