$A$ hot source emits maximum radiation energy at a wavelength of $11 \times 10^{-5} \ cm$. According to Wien's displacement law,for what value of $n$ will a source at a temperature $n$ times the original temperature emit maximum energy at a wavelength of $5.5 \times 10^{-5} \ cm$?

Which graph represents the $v_m - T$ relationship for a black body,where $v_m$ is the frequency corresponding to the maximum energy emission and $T$ is the absolute temperature?

$A$ 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 $b = 3 \times 10^{-3} \ m \cdot K$)

Four pieces of iron heated in a furnace to different temperatures show different colours listed below. Which one has the highest temperature?

$A$ black body is at a temperature of $2880\;K$. The energy of radiation emitted by this object with wavelength between $499\;nm$ and $500\;nm$ is ${U_1}$,between $999\;nm$ and $1000\;nm$ is ${U_2}$ and between $1499\;nm$ and $1500\;nm$ is ${U_3}$. The Wien's constant $b = 2.88 \times {10^6}\;nm\,K$. Then

Two stars emit maximum radiation at wavelengths $3600 \mathring A$ and $4800 \mathring A$ respectively. The ratio of their temperatures is: