What changes are observed in the color of iron as it is heated,and how does the frequency of the emitted radiation change?

(N/A) As iron is heated,its color changes with temperature: $Dull \ Red$ $\rightarrow Bright \ Red$ $\rightarrow White$ $\rightarrow Blue$. As the temperature increases,the wavelength of the emitted radiation decreases,which means the frequency $(v)$ of the emitted radiation increases.