Answers for HSC04 Astrophysics (1 Viewer)

trina_288

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Hi, just wondering if anyone could post up some of the answers for this option.
Particularly part d) ii and iii.

Thanks
 

helper

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d ii)
m1+m2=4PI*2r3/GT2
4x1030=4PI*2r3
Gx(6*24*06*60)2x4x1030=4OI*2r3
r3=Gx(6*24*06*60)2x4x1030/4PI*2
 

helper

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d iii), I will have to check but I think. 2=dwarf

I1/r12=I2/r22
99/r12=1/r22
r22/r12=1/99
r1/r1=1/square rt 99
 

trina_288

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Thanks... although i don't understand part iii) Not your answer, the question in general.
 

helper

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The Intensity of the light coming from a binary system is the sum of the light intensity from the two stars. When one star passess in front of the other, it will eclipse the star.

So when the second star goes in front of the dwarf, the total intensity will drop by the intensity of the dwarf, as no light will be received from it at that point. So the Intensity of that point, gives you the intensity of the main star.

At all other points, the intensity will be the combination of the two.

Have a look at:
http://instruct1.cit.cornell.edu/courses/astro101/java/eclipse/eclipse.htm
 

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