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Questions
Why do the faces of persons sitting around campfire appear to shimmer?
Explain the following:
Why do the faces of people sitting around campfire appear to shimmer?
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Solution
The rays coming from the face of the person, sitting across the campfire, suffer refraction on passing through hot air. Thus, we see the apparent image of the person. Since hot air is in motion, therefore its optical density changes, which in turn shifts the image rapidly. This rapidly shifting image gives a shimmering effect.
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