Question

what is effect on the interference fringes in a young double slit experiment due to following
(1)screen is moved away from the plane of the slits.
(2)the monochromatic source is replaced by another monochromatic source of shorter wavelength
(3) the monochromatic source is replaced by another monochromatic source of longer wavelength
(4)slit width is increased.
(5)monochromatic light is replaced by white light.

Answer 1

$$\begin{gathered} Bandwidth: \\ \beta =\left(\frac{D}{d}\right)\lambda \\ where \\ DisDis\tan cebetweenscreentoslits \\ disDis\tan cebetweentheslits \\ \lambda iswavelength \\ \left(1\right) \\ Screenismovedaway--Here,Dincreases \\ Hence,bandwidthincreases \\ \left(2\right) \\ Wavelengthdecreases--Here,\lambda decreases \\ Hence,bandwidthdecreases \\ \left(3\right) \\ Wavelengthincreases--Here,\lambda increases \\ Hence,bandwidthincreases \\ \left(4\right) \\ Slitwindthincreases--Here,dincreases \\ Hence,bandwidthdecreases \\ \left(e\right) \\ Monochromaticisreplacedwithwhitelight--Maxbrightnessoccursatthecentre \end{gathered}$$