Neet Solved Paper 2015 Question 15
Question: On observing light from three different stars P, Q and R, it was found that intensity of violet colour is maximum in the spectrum of P, the intensity of green colour is maximum in the spectrum of R and the intensity of red colour is maximum in the spectrum of Q. If $ T _{P},T _{Q} $ and $ T _{R} $ are the respective absolute temperatures of P, Q and R, then it can be concluded from the above observations that
Options:
A) $ T _{P}>T _{Q}>T _{R} $
B) $ T _{P}>T _{R}>T _{Q} $
C) $ T _{P}<T _{R}<T _{Q} $
D) $ T _{P}<T _{Q}<T _{R} $
Show Answer
Answer:
Correct Answer: B
Solution:
- We know from Weins displacement law $ {\lambda_m}T $ = constant So. $ T\propto \frac{1}{{\lambda_m}} $
As, $ {\lambda_r}>{\lambda_g}>{\lambda_v} $
So, $ T _{r}<T _{g}<T _{v} $
Given $ P\to {v _{\max ‘}},Q\to {r _{\max ‘}}R\to {g _{\max }} $
Hence, $ T _{Q}<T _{R}<T _{P} $ i.e. $ T _{P}>T _{R}>T _{Q} $
