Astronomy Olympiad


by ritwik06
Tags: astronomy, olympiad
ritwik06
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#1
Jan29-07, 06:48 AM
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Recently I gave my Astronomy Olympiad. There were some questions of descriptive type. If you all dont mind I would like to discuss them here.
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russ_watters
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#2
Jan29-07, 09:09 AM
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Shoot.........
ritwik06
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Jan29-07, 11:07 PM
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Quote Quote by russ_watters View Post
Shoot.........
Here goes the first...
A satellite is 36000 Km away from the equator. What will be the maximum latitude from which the satellite can be viewed.
Well, if it had been a question of geometry, I would have just calculated the angle for cos-1 (6400/42400). My answer would come 81.1...

But what I wrote is about the stability of the satellite. Will the satellite be stable at an altitude of 36000 Kilometres. What do you think??

russ_watters
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Jan29-07, 11:39 PM
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Astronomy Olympiad


It doesn't matter if it is stable or not - it is at 36000km right now.
ritwik06
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Jan30-07, 12:51 AM
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Quote Quote by russ_watters View Post
It doesn't matter if it is stable or not - it is at 36000km right now.
OK :D It means I was foolish to prove that the satellite was unstable. anyways, here goes the second question:
Light passes through a box containing an arrangement of 4 plane mirrors. If the box is removed, even then light doesnt change its path. Is there more than 1 arrangments possible? What will be the sum of all the angles of incidence and reflection.
I think that more than 1 arrangement is possible. And the sum should always be a constant. Probably 360 degree. Whadda say?
Gokul43201
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Jan30-07, 03:12 AM
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Quote Quote by ritwik06 View Post
I think that more than 1 arrangement is possible. And the sum should always be a constant. Probably 360 degree.
I agree on the first but disagree with the second. I can make any sum from 180* to 720*.
ritwik06
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#7
Jan30-07, 09:57 PM
P: 586
Quote Quote by Gokul43201 View Post
I agree on the first but disagree with the second. I can make any sum from 180* to 720*.
Oh very well!! thanks for that :D The third question.
If a shell of iron just floats inside water. Find the ratio of the outer radius to the inner radius. (Density of iron: 7.87 g/cc)
I have assumed that the shell is spherical. And the the space inside the shell is vacuum. Am I going in the right direction?


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