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.

russ_watters
Mentor
Shoot.........

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
Mentor
It doesn't matter if it is stable or not - it is at 36000km right now.

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? :tongue2:

Gokul43201
Staff Emeritus
Gold Member
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*.

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?