If you see the picture is very simple actually there is a you know this is video class we have problem of showing this demo, you have this line here you know, this line is here, I as spare it and pull it down see I have, I will show you here this this is my spectrum here as I shift it I just push it down like that, that is all. I mean I have a graph here, I pull it down and spread it and as 90 degree it has become 0 and now this graph that I have got exactly having the same area as the first graph. So, meaning that the energy of the wave is exactly same.
So, it is something