00:01
Good day.
00:01
The topic is about electromagnetic radiation.
00:04
Electromagnetic radiation can be defined with a certain set of lambda and f which pertains to the wavelength and frequency respectively.
00:13
Lambda and f are related using the following equation where lambda is the wavelength, c is the speed of the electromagnetic radiation, and since it travels in the speed of light, so we have it as the speed of, light which is equal to around 3 times 10 to the power of 8 meters per second and that f is the frequency so the units are as follows so say we have a radiation which wavelength is 10 micrometer and we wish to find the frequency for that so given wavelength is 10 micrometer or since it's micro row, that means 10 to the negative 6 alpha meter.
01:14
We will find the frequency.
01:17
So wavelength, from the wavelength equation, wavelength equals c over f, we can rearrange this to get f equals c over lambda.
01:29
So 3 times 10 to the power of 8 over 10 times 10 to the negative 6.
01:36
And this gives us 3 times 10 to the power of 13 seconds to the negative one or in other unit hurts next what if we're given with frequency which is equal to 5 .5 times 10 to the 14 so wavelength will be solved as c over f so that's 3 times 10 to the power of 8 over 5 .5 times 10 to the power of negative 14 or i should say it should be positive 14 so this is positive 14 right so three times set of the power of 8 over 5 .5 to the power of 14 solving gives us 5 .45 times 10 to the negative 7 and the unit is meters so we note that we can also express this in terms of micrometer just to compare this with the wavelet in the first problem so so again, one meter or one micrometer is composed of 10 to the negative 6 meter.
03:07
So we have it as 5 .45 times 10 to the negative 7 meter.
03:15
So 10 to the negative 6 meter makes one micrometer...