Definitions [2]
Definition: Electromagnetic Waves
Electromagnetic waves are self-propagating transverse waves consisting of oscillating electric and magnetic fields that do not require a medium for propagation.
A signal of 5 kHz frequency is amplitude modulated on a carrier wave of frequency 2 MHz. The frequencies of the resultant signal are ______.
A signal of 5 kHz frequency is amplitude modulated on a carrier wave of frequency 2 MHz. The frequencies of the resultant signal are 2005 kHz, 2000 kHz and 1995 kHz.
Explanation:
Amplitude modulated wave consists of three frequencies are ωc + ωm, ω, ωc - ωm
i.e. 2005 kHz, 2000 kHz and 1995 kHz.
Key Points
Key Points: Electromagnetic Waves
- EM waves are transverse
- E ⟂ B ⟂ direction of propagation
- E and B are in phase
- Speed:
\[c=\frac{1}{\sqrt{\mu_0\varepsilon_0}}=3\times10^8\mathrm{m/s}\] - Poynting Vector:
\[\vec{S}=\frac{\vec{E}\times\vec{B}}{\mu_{0}}\] -
Intensity:
\[I=\frac{1}{2}c\varepsilon_0E_0^2\]
