00:01
So this question, it asks, by what percent is the speed of blue light lessens the speed of the red light? so first, let's try to write the equation for finding the percentage.
00:20
So let's say, how is it? so let's have the difference between the blue light and the red light is v -red minus v -blue.
00:31
And by what percent is blue light less than red light? so it's divided by b red.
00:41
Yeah.
00:42
So this, firstly, let's be sure.
00:43
This is the equation we will be calculating.
00:47
And the two numbers we need is the velocity of red light and the velocity of blue light in silicate glass.
00:56
And we're given this figure.
00:59
It's at the end of, um, section chapter 24 section 4 so from this we can read out silicate flink glass is this top line and let's try to find what refractive index they have blue light is 450 so that's here blue 450 and if we go all the way up it's here and we'll try to draw a line this is 1 .6 1 234 so and blue equals 1 .64 what about actually let's say it's zero because it seems to be exactly here it's not like in the middle of two marks what about red in red um we have 680.
02:07
So 6.
02:09
This is 650.
02:11
2, 3, 4.
02:12
80 is around here.
02:14
Again, we draw a line.
02:17
I'm doing it by hand.
02:18
You should be using a ruler.
02:22
It's here...