Question

A black body is at a temperature of 2880K. The energy of radiation emitted by this object with wave length between 499 nm and 500 nm is U₁, between 999 nm and 1000 nm is U₂ and between 1499 nm and 1500 nm is U₃.

Wein constant b=2.88 x 10⁶nmK. Then

• A. U₁ = 0
• B. U₃ = 0
• C. U₁ = U₂
• D. U₂> U₁

Answer 1

Answer: (D)

U₂> U₁

Answer 2

From wine’s Law constant. Where T is temperature of black body and is wavelength corresponding to maximum energy of emission.

Energy distribution of blackbody radiation is given below :

1. $\mathrm { U } _ { 1 }$ and are not zero because a blackbody emits nearly radiation’s of all wavelengths.

2. Since $\mathrm { U } _ { 1 }$ corresponds lower wavelength and corresponds higher wavelength and corresponds medium wavelength. Hence $U _ { 2 } > U _ { 1 }$ .