Speed of wave

1. Sep 12, 2007

ArielGenesis

In a theoretical wave that does not need a medium, not necessarily EM.
the speed of the wave is given by : v=fl
where f is frequency and l is lamda, wave length

suppose there is a stationary wave generator, we can easily measure f and l from any arbitrary point.
if we move towards the generator we will experience a Doppler effect, lets say, we move in such a way that we hear the frequency 2f. by doing this, the wavelength we detect become 0.5l and thus the speed is still v. so shouldn't any wave have a constant speed disregarding the frame of reference?

2. Sep 13, 2007

Ich

The speed of such a wave is v=E/p, which is frame-dependent except for particles (quanta) of rest mass 0.

3. Sep 13, 2007

bernhard.rothenstein

theoretical wave but what?

Could you define such a wave? The frequency is defined by the source and the wave length by the source and the medium as well!

4. Sep 13, 2007

ArielGenesis

so the wavelength is defined by the medium, that's new!

sorry Ich, but I have no idea what you are about. pardon me but not every one here, especially me, got a degree in physics.

hummm could I define such a wave? I might...
1. I am not sure, a gravitational force wave, where there will be a stationary source object which m=sin(t) where m is mass and t is time/.
2. I am sure! a normal sound wave in a super-fluid, so there will be no viscosity...

is EM is the only wave without medium?