A black body has maximum wavelength λm at temperature 2000

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A black body has maximum wavelength λ_m at temperature 2000 K. Its corresponding wavelength at temperature 3000 K will be

1. 3 λ_m
  2
2. 2 λ_m
  3
3. 4 λ_m
  9
4. 9 λ_m
  4

Correct Option: B

According to Wein's displacement law,
λ_mT = 2.88 × 10^–3
When T = 2000 K,
λ_m (2000) = 2.88 × 10^–3 ....(1)
When T = 3000 K,
λ'_m (3000) = 2.88 × 10^–3 ....(2)
Dividing (1) by (2),

	2		λ_m	= 1 ⇒	λ_m	=	3	⇒ λ'_m =	2	λ_m
	3		λ_m		λ'_m		2		3