Jump to content
  • Join the online East Midlands astronomy club today!

    With active forums, two dark sites and a knowledgeable membership, East Midlands Stargazers has something for everyone.

Angles


dawson
 Share

Recommended Posts

Not sure this is coffee shop talk, but wasn't sure where else to post it!


 


This relates to me setting up my foreground in Stellarium.


 


I'm not too hot on maths and can't get my head around this, and I thought there would be a geek or two here who might be able to work this out for me :)


 


Can you tell me the angle at which both the orange line and the green line hits the red line in the illustration below. The orange line hits the red line at 3 feet above the ground, the green line hits the red line at 5 feet above the ground.


 


Thanks for any replies.


 


James


 


 


Link to comment
Share on other sites

I don't know where the line hits the floor, if I did even I could figure that one out :)    well I could plug the numbers into an online calculator.

 

I posed the same question on another forum I belong to and one bright spark has come up with the solution:

 

"If x is the distance between the red line and the intersection of the yellow line with the baseline then

3/x = 30/(23+x)

which gives x = 23/9

arctan (3/23/9) = arctan(27/23) = 49.57 degrees

And the same for y (distance between the red line and the intersection of the green line with the baseline then)

5/y = 30/(23 + y)

y = 23/5

arctan (5/23/5) = arctan (25/23) = 47.39 degrees"

Link to comment
Share on other sites

Your friend on the other forum gave the angles between the horizontal baseline and the coloured lines. I gave the angles between the red vertical line and the coloured lines. So you have both. Cheers, Pete.

Link to comment
Share on other sites

You're welcome James. I enjoy working these things out like some people do crossword puzzles (which I struggle with).


 


I used to think I was pretty good at maths until my daughter got an A star in GCSE maths at just 15, a year ago in year 10, which is a year earlier than most of her school friends.  She say's it's all my fault :D .


Link to comment
Share on other sites

I don't get it either Pat :)

 

Pete, I'm not even good at crosswords!

 

James

Well, you've done a fantastic job on your other thread explaining how to do custom foregrounds.

That is really helpful, might have a go at that now, thanks James.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.