1. A black body is at a temperature of \(5760 K\). The energy of radiation emitted by the body at wavelength \(250 nm\) is \(U_1\),at wavelength \(500 nm\) is \(U_2\) and that at \(1000 nm\) is \(U_3\) Wien's constant, \(b = 2.88 × 10^6nmK\) . Which of the following is correct?