00:01
Hello, so if you consider these two waves, so wavelength is the distance between two crest, okay? if you measure from this side up to that side right there, and you compare that, sorry, and you compare that with the green one.
00:31
Obviously just by sight, you will see that the red one is longer, right? we say that wave a so if you come here say that wave a has a longer wavelength okay then secondly we want to calculate what the wavelength okay so we know that v equals f lambda so the wavelength is going to be v over frequency but we don't have the frequency yet okay so what we can do is that the length the whole length is what so it's 1 .6 times 10 to the negative 3.
01:18
And how many wavelengths do we have in? we have 1, we've got 2, we got 3, and we got 4, okay? so if you come here, instead of we have a number of waves to be 4, that's the length.
01:32
So if you want the wavelength for just 1, it is going to divide by 4, right? and it's going to give it that.
01:39
So that's the wavelength, okay, of a.
01:44
And we can do the same thing for b right if you count for b it's going to be from here one two three four five six seven eight okay so for with b we're gonna be divided by eight so that's what you see here and that'll be the wavelength so now that we know the wavelength you can of course find the frequencies now okay uh so if you want to know so remember i said that v equals f lambda right so lambda equals v over f remember that this are electromagnetic waves so their speeds are the same it's constant speed of light okay so the little thing that's going to change is the wavelength and the frequency so of course if you want to know which one has a higher frequency so you realize that if you have a very high frequency you have a low wavelength and vice versa okay let me just isolate f so initially we said that a has a higher wavelength if a has a higher wavelength there's going to have a very small frequency because this an inverse relation okay so um so like i said with b has a higher frequency okay because it has a shorter wavelength so now we can find the energy using e equals h f in the frequency or you can use i mean people use uh instead of f people also use noon is the same thing uh so we can find the energy and uh you know each as a plant's constant okay it is given by this value right here ups which is given by this value right here okay so um let's see.
04:03
So that's for the energy of a.
04:08
You can find the energy of b using the same procedure.
04:13
Okay.
04:15
Like i said, the velocity is always f -lamda...
