If temperature of sun is decreased by $1 \%$ then the value of solar constant will change by ........... $\%$
A$2$
B$-4$
C$-2$
D$4$
Medium
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B$-4$
b (b)
Solar constant $\propto T^4$ $\left[\because S=\left[\frac{R}{r}\right]^2 \sigma T^4\right]$
$\frac{\Delta S}{S}=\frac{4 \Delta T}{T}$
and $\frac{\Delta T}{T}=-1 \%$ [given]
So $\frac{\Delta S}{S}=-4 \%$
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