Hello

 

What is the frequency of a pulse ??

 

I mean >> If we have a wave (crest and trough)

and a pulse (crest)

 

which have the same speed

 

what is the wavelength of the pulse and the frequency

 

Do we say that two pulses are equall to one wave

 

so if we have 8 pulses in a second then the frequency is 4 hz

 

or is it 8 hz ?

?????

 

Another one

 

We have two identical waves put the difference in phase is 180

 

they spread in two opposite directions

 

What hapens to them when they meet ?

 

and what if the different in phase is 360 ?

If you have a pulse in time, its frequency will be the Fourier transform of the pulse shape. The wavelength can be found from the frequency as normal.

 

If you have 4 pulses in 1 second you would have a repetition frequency of 4Hz.

 

You'll have to explain your second post a bit more, sorry, but I think what you want to do is read about constructive and destructive interference.

If you have a pulse in time, its frequency will be the Fourier transform of the pulse shape.

 

Its complicated, but I think you mean its shape will be defined by Fourier analysis of the frequencies that together give the pulse its shape? I agree that the number of pulses per second is properly called pulse repetition frequency (prf) although this is commonly described as the frequency of the pulse train.