MCQ
Consider sunlight incident on a slit of width ${10^4}\,\mathop A\limits^o $. The image seen through the slit shall
  • A
    be a fine sharp slit, white colour at the centre
  • B
    a bright slit white at the centre diffusing to zero intensities at the edges
  • a bright slit white at centre diffusing to regions of different colours
  • D
    only be a diffused slit white in colour

Answer

Correct option: C.
a bright slit white at centre diffusing to regions of different colours
c
since the width of slit is comparable to that of wavelength diffraction occurs with maxima at centre. Therefore, at the centre all colours appear i.e, mixing of colours from white patch at centre

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