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Question
The smoke from a fire looks white. Which of the following statements is true?
1) Molecules of the smoke are bigger than the wavelength of light
2) Molecules of the smoke are smaller than the wavelength of light.
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Solution
The smoke from a fire looks white because molecules of the smoke are bigger than the wavelength of light, scatter the light off all wavelengths of white light to the same extent.
Therefore, statement-1 is true.
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