Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
Home  >>  JEEMAIN and AIPMT  >>  Physics  >>  Class12  >>  Wave Optics
0 votes

White light is used in a YDSE with $D= 1m$ and $d= 0.9 mm$ .Light reaching the screen at position $y= 1 mm$ is passed through a prism and its spectrum is obtained. The missing lines in the visible region of this spectrum is :-

$(a)\;300\;nm \\ (b)\;600\;nm \\ (c)\;both \;a\; and\; b \\ (d)\;None $

Can you answer this question?

1 Answer

0 votes
$\Delta P= \large\frac{yd}{D}$
$\qquad= 900 nm$
for minima $\Delta P = \large\frac{(2n-1) \lambda}{2}$
=> $\lambda =\large\frac{2 \Delta P}{(2n-1)}=\frac{1800}{2n-1}$
$\qquad=\large\frac{1800}{1} , \frac{1800}{3}, \frac{1800}{5}, \frac{1800}{7}$
of these $600,360\;nm$ lie in visible region.
Hence these will be missing lines in the visible spectrum.
Hence c is the correct answer.
answered Feb 13, 2014 by meena.p

Related questions

Ask Question
student study plans
JEE MAIN, CBSE, AIPMT Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App