Optics grating element

I am pretty much sure, you will definately get the concept of grating element of a grating, after having a look at my solution. I have explained each and everything as much as I ca...

1line means one slit (a+b) so 4000lines means 4000slits and it makes grating .. here in the question it is given 4000lines to the cm (sometimes it is written like " 4000line per cm...

Grating element it's a distance between centre of two consecutive slits d . d = a (distance between the two slit) + b (slits width) ......................and think the c...

The figure shows a small portion of a plane diffraction grating. The width of each slit is a and opaque spacing between two consecutive slits is. b. a+b is called grating element o...

so it's a defination that (a+b) = 1/ no of gratting lines. see the attached.