Option: Astrophysics (1 Viewer)

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It's true.
My Physics teacher forsaw it.
They've assessed you on practical work in Astrophysics as they did in the Biology and Chemistry electives.

I didn't like this year's Astrophysics that much.
 

Chinmoku03

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I didn't mind it, altho I know I went wayyy overboard with the "How to identify binaries" question. Seen the essay question before in past papers, but was still a bit surprised. Meh

The rest of it seemed fine IMO ^.^
 

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Binaries, they're two stars which orbit a common centre of mass and obey the Universal Law of Gravitation, that better answer it.
I then briefly outlined the 4 types (Visual, spectroscopic, astrometric and eclipsing)
 

jason21

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I mentioned the 4 binaries too but went into a bit of detail for a 2 marker!!!! lol

Astro was pretty straight forward i believe except for (a) (ii) which i couldn't do. The one about the apparent magnitude form Saturn.

And what where the 2 star types you got for the last question?? I rushed to finish and didnt have to time to check over answers, i did Sirius A - sun like mass star, Arcturus - low mass star
 

rainonmay

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I didn't mind the experiment question itself but it was only worth 2 marks. It took me like 6 minutes to write out a description of the experiment =/ That question was a waste of time.
 

conroy1234

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bloody H-R diagram. i thought they'd just make us interpret one
mine was kinda dodge
whoops!
 

J Biddy

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My H-R diagram took me ages; I drew it up and it looked wrong before I worked out the scale was supposed to be logarithmic. Other than that it wasn't too bad, although I'm not sure but I think they wanted you to talk more about active/adaptive optics for the essay question, so maybe I didn't do so well there.....
 

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J Biddy said:
My H-R diagram took me ages; I drew it up and it looked wrong before I worked out the scale was supposed to be logarithmic. Other than that it wasn't too bad, although I'm not sure but I think they wanted you to talk more about active/adaptive optics for the essay question, so maybe I didn't do so well there.....
I didn't use a logarithmic scale. :(
I evaluated adaptive optics and photomultipliers.
 

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Aargh, that calculation on apparent magnitude threw me off so much, because distance should be done in parsecs and they gave you AU. Apparently, because of the numbers they gave you, it would still work out the same using AU insted of parsecs, which means that people who didnt actually know that would have gotten it right anyway... AARGH punishing the people who know their stuff but rewarding those who don't....
 

J Biddy

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I did radio telescopes and CCD's, which I think is way off.....

How did everyone do the question with the Sun's magnitude as viewed on Saturn...?
 

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Crusader said:
Aargh, that calculation on apparent magnitude threw me off so much, because distance should be done in parsecs and they gave you AU. Apparently, because of the numbers they gave you, it would still work out the same using AU insted of parsecs, which means that people who didnt actually know that would have gotten it right anyway... AARGH punishing the people who know their stuff but rewarding those who don't....
Haha I used the values given as AU straight off.
 

oconnor

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ok well...

a prac work? that was really gay, considering my class didnt even do one. my physics teacher got all out of wack and ended u pnot showing us astro, jsut did the main 4. I learned as much astro by myself last night as I could..
 

J Biddy

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I just converted Au to pc and then did the equation. But having just done it again it seems it works straight anyway....
 

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i'm hoping for a 22/25 cause i left out the saturn sun intensity question. Probably could have done it after 20 mins of staring but i couldn't afford the time. How does everyone else think they went? :wave:
 

barling89

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i'm hoping for a 22/25 cause i left out the saturn sun intensity question. Probably could have done it after 20 mins of staring at blankness, but that 'might' have been time wasting. How does everyone else think they went? :wave:
 

gizmo99

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Yo took me ages to work that one out but i think i got it:

u know saturn was 10 times further away than earth so using inverse square law its 1/100 times as bright... then u use the intensity ratio thing and u can work out the suns apparent mag from there! simple... kinda
 

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gizmo99 said:
Yo took me ages to work that one out but i think i got it:

u know saturn was 10 times further away than earth so using inverse square law its 1/100 times as bright... then u use the intensity ratio thing and u can work out the suns apparent mag from there! simple... kinda
That's EXACTLY what my Physics teacher said. :(
 

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I didn't use a logarithmic scale. :(
I evaluated adaptive optics and photomultipliers.
Some people in my class wrote about photoelectric n photographic methods but i don't see how you could really suit it to the question

I did adaptive optics and interferometry
 

ravdawg

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If you understand where the distance modulus formula came from the q comes out:

M = m - 5log (d/10), as d is in parsecs and you know M is magnitude 10 pc away the formula in other words is:

m1 = m2 - 5log (d2/d1), sub in values and you get the answer. THe thing thoguh with this qustion was that if you didn't know d was in parsecs you wouldve got the right answer...

Kinda screwed over the people knew that, and helped the people who didn't!
 

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