Two identical balls $A$ and $B$ are heated. Ball $A$ appears blue and ball $B$ appears red. What is the relationship between their temperatures?

$A$ black body at a temperature of $1640 \ K$ has the wavelength corresponding to maximum emission equal to $1.75 \ \mu m$. Assuming the moon to be a perfectly black body,the temperature of the moon,if the wavelength corresponding to maximum emission is $14.35 \ \mu m$,is ...... $K$.

$A$ black body at a temperature of $3000 \ K$ cools down. The wavelength corresponding to maximum energy density shifts by $\Delta \lambda = 9 \ \mu m$. What is the new temperature of the black body (in $K$)? (Given $b = 3 \times 10^{-3} \ m \cdot K$)

The colour of a shining bright star is an indication of its

If at temperature $T_1 = 1000 \ K,$ the wavelength is $1.4 \times 10^{-6} \ m,$ then at what temperature in $K$ will the wavelength be $2.8 \times 10^{-6} \ m$?

Two spherical stars $A$ and $B$ emit blackbody radiation. The radius of $A$ is $400$ times that of $B$ and $A$ emits $10^4$ times the power emitted from $B$. The ratio $(\lambda_A / \lambda_B)$ of their wavelengths $\lambda_A$ and $\lambda_B$ at which the peaks occur in their respective radiation curves is