When two narrow slits separated by a small distance are illuminated by a light of wavelength ` 5 xx 10^(-7)` m , interference fringes of width `0.5` mm are obtained on a screen . What should be the wavelength of light source to obtain fringes `0.3` mm wide , if the distance between the screen and the slits is reduced to half of the initial value .

Answer

`6 xx 10^(-7)`m