Question

A single slit is illuminated by light of wavelength 6000 $\stackrel{0}{A}$. The slit width is 0.1 cm and the screen is placed 1 m away. The angular position of ${10}^{th}$ minimum in radian is:

• A. $2\times {10}^{-4}$
• B. $6\times {10}^{-3}$
• C. $3\times {10}^{-3}$
• D. $1\times {10}^{-4}$

Answer 1

Answer: (B)

$6\times {10}^{-3}$

Here, n =10, $\lambda =6000\stackrel{0}{A}=6\times {10}^{-7}m$,
d = 0.1cm =${10}^{-3}$m

Angular position of ${10}^{th}$ minima,

$\theta =\frac{n\lambda }{d}=\frac{10\times 6\times {10}^{-7}}{{10}^{-3}}=6\times {10}^{-3}$ rad