The fraunhofer diffraction pattern of a single slit is formed at the focal plane of a lens of focal length 1m. The width of the slit is 0.3 mm. if the third minimum is formed at a distance of 5 mm from the central maximum then calculate the wavelength of light.

Explanation

`x_n=(nf lamda)/a`
`implieslamda=(aX_n)/(fn)=(3 times10^-4 times 5 times10^-3)/ (3 times1)=5000A^@`
`[ because n=3]`