﻿ Two stars P and Q have slightly different surface temperatures TP and TQrespectively, with TP > TQ. Both stars are receding from the earth with speeds vP and vQ relative to the earth. The wavelength of light at which they radiate the maximum energy is found to be same for both: : Kaysons Education

# Two Stars P and Q have Slightly Different Surface Temperatures TP and TQrespectively, With TP > TQ. Both Stars Are Receding From The Earth With Speeds vP and vQ relative To The Earth. The Wavelength Of Light At Which They Radiate The Maximum Energy Is Found To Be Same For Both:

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## Question

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Correct option is

Let  and  be the actual wavelength at which P and Q radiate maximum energy. By Wien’s law,

As these wavelengths appear equal on reaching the earth,  has increased more than  Hence

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