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If λm represents the wavelength at which a black body emits radiation most strongly at temperature T K, then which relation is true?

1. λm varies inversely with T
2. λm is proportional to T⁴
3. λm does not depend on T
4. λm is directly proportional to T

Correct answer: λm varies inversely with T

Solution

Wien's law gives lambda_m * T = constant, so lambda_m is inversely proportional to T (it decreases as temperature rises).

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