Question

When a beam of white light passes through a prism, the colour that undergoes the leastdeviation, is

Answer 1

Actually,when a white light undergoes deviation the red colored light experiences least deviation. This can be remembered by the word VIBGYOR where:-
V-Violet
I-Indigo
B-Blue
G-Green
Y-Yellow
O-Orange
R-Red
Hence, Violet undergoes maximum deviation and Red undergoes minimum deviation.

Answer 2

the red colour is the one which is least deviated..

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