0:00
Hi there.
00:01
So for this problem, we are told that a glass plate, it has a thickness that we are going to call t of 2 .5 millimeters, and this is equal to 2 .5 times 10 to the minus 3 meters.
00:24
And a refract in this of the glass is equal to 1 .4.
00:35
So the wavelength of life.
00:38
In vacuum is equal to 400 and 400, 540 nanometers that we can write in meters as 540 times 10 to the minus 9 meters.
01:03
Now, the distance between the source and the screen is also given, and that value, we're going to call it d, d is equal to, 1 .80 centimeters, which in meters is equal to 1 .8 times 10 to the minus 2 meters.
01:28
So the question for this problem is how many wavelengths are there between the source and the screen? now, the wavelength of the line median first can be obtained by the wavelength that we're going to call it the wavelength and the medium that in this case is in the glass.
01:58
So we're going to call it the wavelength in glass.
02:01
It's equal to the wavelength and vacuum that we are given that value, divided by the index of refraption of glass.
02:12
So if we substitute those two values, we will have 540 times 10 to the minus 9 meters, divided by the index of refraption of the, the glass that is equal to 1 .4.
02:26
So from this, we obtain a value of 385 .71 times 10 to minus 9 meters.
02:39
Now, the number of wavelengths in the glass that we are going to call the number n1 is equal to the thickness divided by the wavelength that we just have obtained.
02:52
So we will have that that is.
02:54
The thickness that we know is 2 .5 times 10 to minus 3 meters divided by the wavelength that is equal to 385 .71 times 10 to minus 9 meters...