When you look into a mirror placed perpendicular to a sunlit floor of water, the wall sometimes shows BANDS of seven colours. This is best explained as:
AThe colours come from the mirror's coating
BThe colours come from the eye
CThe mirror + water layer acts as a prism, dispersing white sunlight into its component colours
DRandom colour reflection
Answer & Solution
Correct answer: C. The mirror + water layer acts as a prism, dispersing white sunlight into its component colours
Sunlight is white — a mixture of seven colours. The slanted water surface above the mirror behaves like a prism: light enters, gets dispersed into its colours, reflects from the mirror, and exits — producing a spectrum on the wall. The same principle gives rainbows (water droplets act as prisms).
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