UPSEE 2019 Solved Paper

Given, wavelength λ1=4000Å and λ2=6000Å
As, Wien's displacement law, λm=

b

T

where, b= Wien's constant and T= temperature
So, λm∝

1

T

Hence,

λ1

λ2

=

T2

T1

So, putting the given values, we get

T1

T2

=

λ2

λ1

=

6000Å

4000Å

⇒

T1

T2

=

3

2

Hence, ratio of temperature is 3:2.