Naked Science Forum

On the Lighter Side => That CAN'T be true! => Topic started by: Cindy2 on 23/03/2009 09:30:02

Title: Can we see radio waves with our eyes?
Post by: Cindy2 on 23/03/2009 09:30:02
Cindy asked the Naked Scientists:
   
Is it possible to see radio waves with naked eyes?

I was hoping maybe you could give me a few hints as to what I should be looking for and what to avoid.  Any info much appreciated.

Thank you.
Cindy

What do you think?
Title: Can we see radio waves with our eyes?
Post by: LeeE on 23/03/2009 13:48:21
Only if you're traveling towards them, or the transmitter is traveling towards you, very quickly so that they get blue-shifted up in to the visible spectrum.
Title: Can we see radio waves with our eyes?
Post by: RD on 23/03/2009 14:36:31
If you rig up a spark gap transmitter* you could see the the spark created by the radio waves in a nearby receiver loop ...


Quote
In 1888 physicist Heinrich Hertz set out to verify Maxwell's predictions. Hertz used a tuned spark gap transmitter and a tuned spark gap detector (consisting of a loop of wire connected to a small spark gap) located a few meters away. In a series of UHF experiments, Hertz verified that electromagnetic waves were being produced by the transmitter. When the transmitter sparked, small sparks also appeared across the receiver's spark gap, which could be seen under a microscope.
http://en.wikipedia.org/wiki/Spark-gap_transmitter


[* Your neigbours will complain about poor TV/Radio reception if you do   [:)] ].
Title: Can we see radio waves with our eyes?
Post by: techmind on 23/03/2009 14:51:10
Cindy asked the Naked Scientists:
   
Is it possible to see radio waves with naked eyes?

I was hoping maybe you could give me a few hints as to what I should be looking for and what to avoid.  Any info much appreciated.

Thank you.
Cindy

What do you think?

Firstly, the eyes are only sensitive to visible light.

The wavelength of radio waves are of the order 10 million times longer than visible light (eg 1.5kilometres for radio 4 longwave, 3 metres for VHF/FM radio, 1.5metres for DAB, 0.5m for TV, 0.25-0.5m for mobile phones) compared to 500nano-metres for visible light.

But even so, with any detector technology it is fundamentally not possible to "image" ie see a picture of where the radiowaves are coming from with any device smaller than a few wavelengths of the wave.
Consequently even if our eyes could "detect" radiowaves we might only detect overall flashes or colours - we couldn't see where they were coming from.

Title: Can we see radio waves with our eyes?
Post by: halbert33 on 06/04/2009 10:47:44
Cindy asked the Naked Scientists:
   
Is it possible to see radio waves with naked eyes?

I was hoping maybe you could give me a few hints as to what I should be looking for and what to avoid.  Any info much appreciated.

Thank you.
Cindy

What do you think?
i think the answer of this question is no.
if you have any idea to see radio waves with naked eyes please tell me.