Transmission Of Heat Question 11

Question: Assertion : Blue star is at high temperature than red star. Reason : Wein’s displacement law states that $ T\propto (1/{\lambda _{m}}) $ .

[AIIMS 2002]

Options:

A) If both assertion and reason are true and the reason is the correct explanation of the assertion.

B) If both assertion and reason are true but reason is not the correct explanation of the assertion.

C) If assertion is true but reason is false.

D) If the assertion and reason both are false.

E) If assertion is false but reason is true.

Show Answer

Answer:

Correct Answer: A

Solution:

From Wein’s displacement law, temperature $ (T)\propto 1/{\lambda _{m}} $ (where $ {\lambda _{m}} $ is the maximum wavelength). Thus temperature of a body is inversely proportional to the wavelength. Since blue star has smaller wavelength and red star has maximum wavelength,

Therefore blue star is at higher temperature then red star.