Question

A black body is at a temperature of 5760 K. The energy of radiation emitted by the body at wavelength 250 nm is U₁,at wavelength 500 nm is U₂ and that at 1000 nm is U₃. Wine's constant, b = 2.88 × 106 nmK. Which of the following is
correct ? [2016]
(a) U₁ = 0 (b) U₃ = 0
(c) U₁ > U₂ (d) U₂ > U₁​

Answer 1

Answer:

The energy of radiation emitted by the body at wavelength 250nm is U1, at wavelength 500nm is U2 and that at 1000nm is U3. Wien's constant, b = 2.88 X 106nmK.

Answer 2

Option d

Explanation:

... [Given]

Temperature, T1 = 5760 K

Since, it is given that energy of radiation emitted by the body at wavelength 250 nm in U1, at wavelength 500 nm is U2 and that at 100 nm is U3

∵ According to Wien's law, we get

λmT = b

Where, b = Wiens constant = 2.88 × 10^6 nmK

=> λ = b/T

=> λm = 2.88 × 10^6 nmK / 5760 K

=> λm = 500 nm

∵ λm = Wavelength corresponding to maximum energy, so U2 > U1