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Universe — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsUniverse1 Mark
Question
Assertion : A star which appears blue will be much hotter than the sun
Reason : lt is based on Wien's law
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Answer

(a) According to Wien's law, $\lambda_m T=b=$ constant. As $\lambda_m$ for the star is blue, which is less than $\lambda_m$ for sun, which is yellow, therefore temp. $T$ of star will be much higher than the temperature of the sun.

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