Consider sunlight incident on a slit of width `10^(4) Å` . The image seen through the slit shall

Options

A. be a fine sharp slit white in colour at the centre
B. a bright slit white at the centre diffusing to zero intensities at the edges
C. a bright slit white at the centre diffusing to regions of different colours
D. only be a diffused slit white in colour

Answer

A

Explanation

Here, the width of the slit is `10^(4) Å`, i.e., `10000 Å`. The wavelength of (visible) sunlight varies from `4000 Å` to `8000 Å`. As width of slit `a gt lambda` (wavelength of light), therefore, no diffraction occurs. The image seen through the slit shall be a fine sharp slit white in colour at the centre. Choice (a) is correct.