How Do Radio Waves Cause Electron Movement in Antennas?

AI Thread Summary
Electrons in an antenna move to generate an induced current when radio waves, which are electromagnetic waves, interact with them. The oscillating electric and magnetic fields of the incoming radio wave exert forces on the electrons, causing them to move back and forth. While the electric and magnetic fields are perpendicular, they do not cancel each other out; instead, the electric field is primarily responsible for the movement of the electrons. The voltage induced in a conductor is related to the length of the conductor and the incoming electric field. Overall, the interaction between the dynamic fields and the electrons leads to the generation of oscillating currents in the antenna.
FilipLand
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Hi!

What exactly makes electrons in the antenna move to generate an induced current which then can be encoded?

Is it radio waves that hits the antenna and makes the electrons move? If so, why/how? :)

All I get from this link is that "the radio waves makes the electrons wiggling back and forth", but how? http://www.explainthatstuff.com/radio.html
 
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Thank you!
I found the same thing here "during reception, the oscillating electric and magnetic fields of an incoming radio wave exert force on the electrons in the antenna elements, causing them to move back and forth, creating oscillating currents in the antenna."

A radio wave is a electromagnetic wave, does not the force from the magnetic field and the electric field (acting on an electron in the antenna) cancel each other out? Because the B and E-field is perpendicular right?
 
FilipLand said:
Thank you!
I found the same thing here "during reception, the oscillating electric and magnetic fields of an incoming radio wave exert force on the electrons in the antenna elements, causing them to move back and forth, creating oscillating currents in the antenna."

A radio wave is a electromagnetic wave, does not the force from the magnetic field and the electric field (acting on an electron in the antenna) cancel each other out? Because the B and E-field is perpendicular right?
FilipLand said:
Thank you!
I found the same thing here "during reception, the oscillating electric and magnetic fields of an incoming radio wave exert force on the electrons in the antenna elements, causing them to move back and forth, creating oscillating currents in the antenna."

A radio wave is a electromagnetic wave, does not the force from the magnetic field and the electric field (acting on an electron in the antenna) cancel each other out? Because the B and E-field is perpendicular right?
My view is that it is the electric field which causes the electrons to move and stationery electrons are not moved by a magnetic field.
The voltage induced on a short conductor can be found by multiplying its length by the incoming E-field.
.
 
FilipLand said:
A radio wave is a electromagnetic wave, does not the force from the magnetic field and the electric field (acting on an electron in the antenna) cancel each other out? Because the B and E-field is perpendicular right?

The E and B fields are perpendicular to each other, but that doesn't cancel out the force on the electrons.

tech99 said:
My view is that it is the electric field which causes the electrons to move and stationery electrons are not moved by a magnetic field.
The voltage induced on a short conductor can be found by multiplying its length by the incoming E-field.

Perhaps, but the electrons are not stationary in an antenna receiving a signal. The electric and magnetic fields aren't static either, so you really have a complicated situation.
 
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