For a crystal, the angle of diffraction (20) is `90^@` and the second order line has a d value of `2.28 A^@`. The wavelength (in `A^@`) of X-rays used for Bragg's diffraction is

Options

A. 1.612
B. 2
C. 2.28
D. 4

Answer

a

Explanation

Angle of diffraction `(2theta) = 90^@ implies theta = 45^@`
Distance between two planes, d = 2.28 `overset(@)(A)` (second order diffraction)
n = 2
According to Bragg's equation, `n lambda = 2d sin theta`
`2 lambda = 2 xx 2.28 xx sin 45^@`
` lambda = 1.612` (Wavelength of X-rays)