Question

Solar radiation emitted by Sun resembles that emitted by a black body at a temperature of $6000K$. Maximum intensity is emitted at wavelength of about $4800$ $A^{\circ }$. If the sun were to cool down from $6000K$ to $3000K$, then the peak intensity would occur at a wavelength

• A. 4800 $A^{\circ }$
• B. 9600 $A^{\circ }$
• C. 2400 $A^{\circ }$
• D. 19200 $A^{\circ }$

Answer 1

Answer: (B)

9600 $A^{\circ }$

From wein's displacement law,we know that ${\lambda }_{max}T=constant$
so we can write ${\lambda }_1{T}_1={\lambda }_2{T}_2$
so${\lambda }_2=\frac{{\lambda }_1{T}_1}{{\lambda }_2}=\frac{\left(4800\right)\times \left(6000\right)}{(6000-3000)}=9600A^0$