Question

White coherent light `(400 nm-700 nm)` is sent through the slits of a YDSE. `D=0.5 mm`, D=50 cm. There is a hole in the screen at a point `1.0 mm` away (along the width of the fringes) from the central line.
(a) Which wavelength will be absent in the light coming from the hole?
(b) Which wavelength(s) will have a strong intensity?

Answer 1

Given `d=0.5mm, D=50 cm and y=1 mm`
(i) For absent wavelength use condition of minima,
`y=(2n+1)(Dlambda)/(2d)`
`rArr 10^(-3)=((2n+1)(0.5)lambda)/(2xx0.5xx10^(-3)`