00:01
Let first draw a diagram to understand in a more clear way.
00:05
So let me this a and name this p and the light ray is coming here and from here to here.
00:14
So let name this as p.
00:16
So the between them is theta 1 and this is theta -dash 1.
00:22
From here to here the length is 1 minus x and from here to here it is x.
00:30
And from here to here the height is h1 and from here to here the height is h2 and this is l.
00:44
So basically let's first consider that the light ray shown in the figure a the ray of light that's starting at a point a reflex of the surface at the point p this is the point b and which is arriving at the point b and the horizontal distance is l and from the point is e.
01:03
So we will write the expression for the time required.
01:06
So this will be t will be equal to whole root over x square plus h1 square divided by c plus whole root over 1 minus x whole square plus h2 square divided by c, which is basically traveling between the two points.
01:25
Let's say equation number one.
01:27
Now here t is the time required and x is the distance of the incidence ray...