For Bragg's differaction by a crystal to occur, then the X-ray of wavelength `lambda` and ineratomic distance d must be

Options

A. `lambda` is greater than `2d`
B. `lambda` equals `2d`
C. `lambda` is smaller than or equal to `2d`
D. `lambda`is smaller than `2d`

Answer

c

Explanation

For bragg's differaction
`2d sin theta=n lambda` or `lambda=(2 d sin theta)/n`
As `0lesin thetale1` so `lambdale2d`