Wave Optics Question 2
Question 2 - 25 January - Shift 1
In Young’s double slits experiment, the position of $5^{\text{th }}$ bright fringe from the central maximum is $5 cm$. The distance between slits and screen is $1 m$ and wavelength of used monochromatic light is $600 nm$. The separation between the slits is:
(1) $60 \mu m$
(2) $48 \mu m$
(3) $12 \mu m$
(4) $36 \mu m$
Show Answer
Answer: (1)
Solution:
Formula: YDSE
Given
$D=1 m$
$\lambda=600 \times 10^{-9} m$
$n=5$
As $y _{nth}=\frac{n \lambda D}{d}$
$\Rightarrow \frac{5 \times 600 \times 10^{-9} \times 1}{d}=5 \times 10^{-2}$
$\Rightarrow d=\frac{5 \times 600 \times 10^{-9} \times 1}{5 \times 10^{-2}}=60 \times 10^{-6} m$
$\Rightarrow d=60 \mu m$
