A black body at 20000 K, emits maximum energy at a wavelength of `1.56 mu m`. At what temperature will it emit maximum energy at a wavelength of `1.8 mu m` ?

Answer

`[1733 K]`

Explanation

Here, `T_(1)=2000 K, lambda_(1)=1.56 mu m`,
`T_(2)=?, lambda_(2)=1.8 mu m`
`lambda_(1) T_(1)=lambda_(2)T_(2)`
or `T_(2)=(lambda_(1)T_(1))/(lambda_(2))=(1.56xx2000)/(1.8)=1733 K`