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Question
The light from the Sun is found to have a maximum intensity near the wavelength of 470 nm. Assuming the surface of the Sun as a black body, the temperature of the Sun is _____________.
[Wien's constant b = 2 .898 x l0- 3mK]
Options
5800 K
6050 K
6166 K
6500 K
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Solution
The light from the Sun is found to have a maximum intensity near the wavelength of 470 nm. Assuming the surface of the Sun as a black body, the temperature of the Sun is 6166 K.
Explanation:
Given: λm= 470nm = 4.70×10−7m b = 2.898×10−3mK
From Wien's displacement law,
Tλm = b
We get, temperature of sun
T = `b/(λ_m)`
∴ T = `(2.898 xx 10^(−3))/(4.70 xx 10^(−7))` = 6166 K
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