From this question, I've noted that an electromagnetic field carries no electric charge but it has two components:
- Electric field
- Magnetic field
Now what I failed to understand is how does the receiving antenna get an induced small voltage. Is it due to the electric or the magnetic field component of EMF? and How?
Answer
If you put an electron in an electric field it moves and this is how a radio wave induces a voltage in the aerial. The oscillating electric field of the waves causes electrons to move in the metal of the aerial and this generates the voltage.
Aerials are normally designed so they have a natural resonance at the frequency of the radio wave, so the strength of the potential gets amplified by the resonance.
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