The amplitude of the magnetic field part of a harmonic electromagnetic wave in vacuum is \(B_0 = 510\ nT\). What is the amplitude of the electric field part of the wave?
The amplitude of the magnetic field part of a harmonic electromagnetic wave in vacuum is \(B_0 = 510\ nT\). What is the amplitude of the electric field part of the wave?
Solution and Explanation
Amplitude of magnetic field of an electromagnetic wave in a vacuum,
\(B_0 = 510\ nT = 510 \times 10^{−9} T \)
Speed of light in a vacuum, \(c = 3 × 10^8 m/s \)
Amplitude of electric field of the electromagnetic wave is given by the relation,
\(E = cB_0 \)
\(E = 3 × 10^8 × 510 × 10^{−9 }\)
\(E = 153 \ N/C\)
Therefore, the electric field part of the wave is \(153\ N/C\).
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Concepts Used:
Electromagnetic waves
The waves that are produced when an electric field comes into contact with a magnetic field are known as Electromagnetic Waves or EM waves. The constitution of an oscillating magnetic field and electric fields gives rise to electromagnetic waves.
Types of Electromagnetic Waves:
Electromagnetic waves can be grouped according to the direction of disturbance in them and according to the range of their frequency. Recall that a wave transfers energy from one point to another point in space. That means there are two things going on: the disturbance that defines a wave, and the propagation of wave. In this context the waves are grouped into the following two categories:
- Longitudinal waves: A wave is called a longitudinal wave when the disturbances in the wave are parallel to the direction of propagation of the wave. For example, sound waves are longitudinal waves because the change of pressure occurs parallel to the direction of wave propagation.
- Transverse waves: A wave is called a transverse wave when the disturbances in the wave are perpendicular (at right angles) to the direction of propagation of the wave.