Question

The second order Bragg diffraction of X-rays with $\lambda =1.0\mathring{A}$ from a set of parallel planes in a metal occurs at an angle $60^{\circ }$. The distance between the scattering planes in the crystals is

• A. $0.575\mathring{A}$
• B. $1.00\mathring{A}$
• C. $2.00\mathring{A}$
• D. $1.17\mathring{A}$

Answer 1

Answer: (D)

According to Bragg- equation,
$n\lambda$=2d sin $\theta$
n=2
$lambda=1$
deflected angle$\theta =60^{\circ }$
$d=?$
Distance between two plane of crystal
$2\times 1=2\times d\times sin60^{\circ }$
$2\times 1=2\times d\times \frac{\sqrt{3}}{2}$
$d=\frac{2}{\sqrt{3}}=\frac{2}{1.7}=1.17\mathring{A}$