Question

The correct relation between the angle of diffraction $\varphi$ and the glancing angle $\theta$ in Davission – Germer experiment will be-

• A. $\theta ={90}^{\circ }-\frac{\varphi }{2}$
• B. $\varphi =\frac{\theta }{2}-{90}^{\circ }$
• C. $\theta ={90}^{\circ }-\varphi$
• D. $\varphi ={90}^{\circ }-\theta$

Answer 1

The correct option is A $\theta ={90}^{\circ }-\frac{\varphi }{2}$



From the figure we get,

$\theta +\varphi +\theta ={180}^{\circ }$

$\Rightarrow 2\theta +\varphi ={180}^{\circ }$

$\therefore \theta ={90}^{\circ }-\frac{\varphi }{2}$

Hence, $\left(A\right)$ is the correct answer.