In a Young's Double Slit experiment, the separation of four bright fringes is 2.5mm, the wavelength of light used is 6.2*10^-7m. If the distance from the slits to the screen is 80cm, calculate the separation of two slits.
I tried applying
4*¥D/d=1.5*10^-3m
But kept getting wrong answer. What's am I doing wrong?
1 answer
You can't use 4*¥D/d=1.5*10^-3m for calculation of d because that formula is for distance between central bright fringe & 4rth bright fringe not for distance between four bright fringes.