Question

why is spectrum seen in prism but not in glass slab?
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Answer 1

HEYY MATE HERE IS UR ANSWER

==> This is because a dispersion takes place in prism and light ray is refracted that is they are bent when it passes through one medium at an angle and changes its speed. When the light passes through glass it has two interfaces one entering and other leaving. So the spectrum is formed by prism not by glass.

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