Confused about this

W

WildStriker

New Member

• Jul 15, 2010

• #1

If you want to work out the wavelength of a wave, how do you first work out the value of 3 X 10^8 m/s for velocity if the method is wavelength = frequency (150Hz) X velocity (3 X 10^8 m/s)?

Comments will be appreciated.

Thanks

 

Last edited: Jul 15, 2010

RCinFLA

Well-Known Member

• Jul 15, 2010

• #2

Wavelength in free space is velocity of light divided by frequency.

For 150 Hz it would be 2.998 x 10^8 / 150 Hz = 2 million meters.

A 500 MHz television signal would be 0.6 meter.

 

W

WildStriker

New Member

• Jul 15, 2010

• #3

So in terms of λ = F X V, whats the value of "3 X 10^8"? Do you work it out asnormal which gives you 300000000?

 

MikeMl

Well-Known Member

Most Helpful Member

• Jul 15, 2010

• #4

How do you work out the number of electrons in a coulomb? Temperature at absolute zero? Temperature at which water freezes/boils?

Hint: they are all physical constants.

 

unclejed613

Well-Known Member

Most Helpful Member

• Jul 16, 2010

• #5

WildStriker said:

So in terms of λ = F X V, whats the value of "3 X 10^8"? Do you work it out asnormal which gives you 300000000?

Click to expand...

yup, that's what the notation means.... and that's in meters per second. quick rule of thumb.... 1 meter= 300Mhz, 10 meter= 30Mhz, 100 meter=3Mhz, etc...
these 1 meter multiples are also the boundaries of the VHF, HF, MF, etc... designations for radio bands.