It is currently Mon Nov 18, 2019 6:30 am


Post new topic Reply to topic  [ 3 posts ] 
Author Message
PostPosted: Fri Jun 17, 2011 9:50 pm 
Offline

Joined: Fri Jun 17, 2011 9:49 pm
Posts: 1
Hi!

Here is my problem: there is a star, for which we know the distance, d=21.2 pc,
the measurement error is delta_d=1.8 pc. The question is that how far should we put this star,
so that the following equation would be true: d/delta_d = 3?
The teacher told me to use two formulas: m-M=-5+5log(d) and pi=1/d (pi=parallax),
and then do some error propagation calculations.
Of course, I have already tried it using the equations above,
but I did not succeed.
Does anybody have any idea?
Actually, it would be OK as well, if anybody could do it using
any other equations.
Thank you, and sorry for my english.

Cheers, Joe


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Sun Jul 03, 2011 3:10 pm 
Offline

Joined: Fri Jul 06, 2007 9:51 pm
Posts: 349
Is it just me or is something missing from this question.


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Sun Jul 03, 2011 6:58 pm 
Offline

Joined: Sat Dec 11, 2004 8:18 pm
Posts: 6505
Location: Manchester
Dear Big_Kev
No! I do not think it is necessarily you ?
One thing that seems to be a possible problem is that the teacher is incompetent, otherwise I would have suggested asking the teacher for advice.
Best wishes from Cliff
PS "think" added above 6th July


Top
 Profile Send private message  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 3 posts ] 

All times are UTC


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group