Question
Question: What are the directions of electric and magnetic field vectors relative to each other and relative t...
What are the directions of electric and magnetic field vectors relative to each other and relative to the direction of propagation of electromagnetic waves?
Solution
Electromagnetic waves are also known as EM waves. When an electric field is made to interact with a magnetic field, electromagnetic waves are produced. Electromagnetic waves are transverse in nature.
Complete solution:
Step I:
The frequency f determines the physical properties of EM waves. However, the size of the wave is determined by its wavelength λ. The wavelength (λ) of an EM wave is the distance between two peaks of either electric or magnetic field. The amplitude of an electromagnetic wave determines the maximum intensity of the field.
Step II:
When an atomic particle, such as an electron, is accelerated by an electric field, EM wave is formed . The movement produces oscillating electric and magnetic fields, in a bundle of light energy called a photon. Photons travel in harmonic waves at the fastest speed possible.
Step III:
In an electromagnetic wave the electric and magnetic field are mutually perpendicular. Both electric and magnetic fields are also perpendicular to the direction of propagation of the wave . For instance , if the direction of electric field and magnetic field is along the Y- and Z- axis then the direction of propagation of EM waves will be in the positive X-axis.
Note: There arises a question why electric and magnetic fields are perpendicular. This is because of Faraday’s Law of electromagnetic induction. As per this law, if a magnetic field is varying then it will produce an electric field which acts in its perpendicular direction. If the electric field is varying, it will produce a magnetic field in its perpendicular direction. That is why they act in a perpendicular direction to each other.