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1. In my CGP guide, it says: "Radio waves used for TV and FM radio transmissions have very short wavelengths (10cm-10m). To get reception, you must be in direct sight of the transmitter - the signal doesn't bend around hills or travel far through buildings."

2. (Original post by blobbybill)
In my CGP guide, it says: "Radio waves used for TV and FM radio transmissions have very short wavelengths (10cm-10m). To get reception, you must be in direct sight of the transmitter - the signal doesn't bend around hills or travel far through buildings."

some waves diffract less than others

3. but do the radio/tv waves require you to be inline with the receiver or not? One says you do, one says you dont.
(Original post by thefatone)
some waves diffract less than others

4. (Original post by blobbybill)
but do the radio/tv waves require you to be inline with the receiver or not? One says you do, one says you dont.
i think the diagram answers that, see the(diagram on the right) one with a longer wavelength diffracts more? that doesn't need to be inline with the receiver since it bends round corner and stuff more.
a shorter wavelength however (diagram on the left) diffracts less and can't reach the reciever so the shorter the wavelength, the less if diffracts, the more it needs to be inline with the reciever
5. (Original post by thefatone)
i think the diagram answers that, see the(diagram on the right) one with a longer wavelength diffracts more? that doesn't need to be inline with the receiver since it bends round corner and stuff more.
a shorter wavelength however (diagram on the left) diffracts less and can't reach the reciever so the shorter the wavelength, the less if diffracts, the more it needs to be inline with the reciever
Yes, and your diagram confirms that. I am asking for with radio waves that are used for TV and FM radio, are they long enough wavelengths to diffract? The CGP says that they are not, whereas the BBC says that they are.

Thanks
6. (Original post by blobbybill)
Yes, and your diagram confirms that. I am asking for with radio waves that are used for TV and FM radio, are they long enough wavelengths to diffract? The CGP says that they are not, whereas the BBC says that they are.

Thanks

maybe this helps?
7. It's not a case of this wave diffracts and that wave doesn't... it's that this (AM radio frequency) wave diffracts more than that (TV frequency) wave

typical AM radio frequency 1.152 MHz ~ 261 m wavelength
typical TV frequency 500 Mhz ~ 0.6 m wavelength

The BBC website is probably written for a less technical audience and is therefore less careful about its terms
8. (Original post by Joinedup)
It's not a case of this wave diffracts and that wave doesn't... it's that this (AM radio frequency) wave diffracts more than that (TV frequency) wave

typical AM radio frequency 1.152 MHz ~ 261 m wavelength
typical TV frequency 500 Mhz ~ 0.6 m wavelength

The BBC website is probably written for a less technical audience and is therefore less careful about its terms
Not probably, definitely.

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