Question

Young's double slit experiment is performed with sodium (Yellow) light of wavelength 589.3 nm and the interference pattern is observed on a 100 cm away The 10th bright fringe has its centre at a distance of 12 nm from the central maximum. The separation between the slits is

• A. 0.49 mm
• B. 0.06 mm
• C. 0.7 mm
• D. 0.53 mm

Answer 1

The correct option is A 0.49 mm

$\begin{array}{c}{n}_{\beta }=12\times {10}^{-3}\\ \Rightarrow 10\times \frac{{\lambda }_0}{d}=12\times {10}^{-3}\\ d=\frac{10\times \lambda \times 1}{12\times {10}^{-3}}\\ =\frac{1000}{12}\times 589.3\times {10}^{-9}\\ =\frac{589.3}{12}\times {10}^{-6}\\ =49.10\times {10}^{-6}m\\ =0.49mm\end{array}$

$\therefore$ Option $A$ is correct.