Find the temperature and total radiancy of star

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Stars behave as perfect blackbodies, with Star A having a surface temperature of 10^12 K. Using Wien's law, the temperature of Star B is determined to be twice that of Star A due to its maximum spectral radiancy wavelength being half. The total radiancy can be calculated based on this temperature. Additionally, a spaceship positioned between the two stars experiences a Doppler shift, indicating that Star B is approaching Star A, and the relative velocity can be derived from the observed wavelength change. Forum participants emphasize the importance of showing prior work when seeking help to foster collaborative problem-solving.
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Thank you in advance for your help!

Stars act like perfect blackbodies. Star A has a surface temperature of 10^12 K. For another star B the wavelength at which the spectral radiancy is a maximum (\lambda_{max})^B is half taht of star A.

a) Find the temperature and total radiancy of star B.(per sq m)

Using Wien's formula
Lambda T = constant

Lambda(A) T(A) = 2 Lambda (B) T(A) = Lambda(B) = T(B)
So the temperature of B is twice that of A

Also since w = 2898micormetres K then i can find out lambda.

C) A spaceship is positioned on the straight line betwen the stars A and B. The spaceship is at rest with respect to star A. Stars A and B have relative velocities such that the spectral radiancy from B appears to be 1/3 rd its wavelength. What is the relative velocity of th stars?

If the wavelength is smaller than B must be approching A(yes?) then the doppler shift formula iwth the + on top would be used.
 
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What have you done so far on any of these problems?
 
Tide said:
What have you done so far on any of these problems?
what do you mean ?

By the way I'm fine i understand this problem quite well, i would appreciate your help with this one

https://www.physicsforums.com/showthread.php?t=49868
 
stunner5000pt said:
what do you mean ?

By the way I'm fine i understand this problem quite well, i would appreciate your help with this one

https://www.physicsforums.com/showthread.php?t=49868

What I mean is that according to the forum rules you should indicate what work you've done so far on the problems for which you are seeking help. People are more than willing to help out if you give some indication of the effort you've made at solving a problem before you post it here but they reluctant to provide outright solutions when problems are posted with no work shown. It's not a homework service!
 
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