My Math Forum  

Go Back   My Math Forum > High School Math Forum > Algebra

Algebra Pre-Algebra and Basic Algebra Math Forum


Reply
 
LinkBack Thread Tools Display Modes
May 20th, 2010, 09:39 PM   #1
Newbie
 
Joined: May 2010

Posts: 4
Thanks: 0

Ellipse radius at specific angle?

Okay, I found some formulas but I did not find any that I would believe, but:
Earth minor radius is at pole and it is 6356.7519km and major radius is 6378.1366km at equator and now I want to know what is radius at my latitude of 60 at Helsinki Finland, how do I calculate this? And please, in simplest way you can say it Thank you.
keijojo is offline  
 
May 21st, 2010, 04:27 AM   #2
Global Moderator
 
Joined: Dec 2006

Posts: 20,469
Thanks: 2038

If the earth's cross-section is an ellipse, its equation is (x/6378.1366km) + (y/6356.7519km) = 1.
For your latitude, y = (?3)x and the radius there is 2x, so substitute for y, find x and then find 2x.
skipjack is offline  
May 22nd, 2010, 04:10 AM   #3
Newbie
 
Joined: May 2010

Posts: 4
Thanks: 0

Re: Ellipse radius at specific angle?

Thank you, but I'm not sure did I understand, I could think my ass off or can you say it in more simplier way and even better I would be very thankful if you would show how its calculated all the way to the answer, but you don't have to if you don't want to or have the time for helping not-so-mathgenious like me
keijojo is offline  
May 23rd, 2010, 09:44 PM   #4
Global Moderator
 
Joined: Dec 2006

Posts: 20,469
Thanks: 2038

What exactly puzzles you? Do you understand that tan(60) = ?3? What did I give that isn't simple?
skipjack is offline  
May 25th, 2010, 07:26 AM   #5
Newbie
 
Joined: May 2010

Posts: 4
Thanks: 0

Re: Ellipse radius at specific angle?

I don't understand what do I have to do with:
1,7320508075688772935274463415059 = tan(60) = ?3,
to get radius?
keijojo is offline  
May 25th, 2010, 11:40 AM   #6
Global Moderator
 
Joined: Dec 2006

Posts: 20,469
Thanks: 2038

You use the equation I gave and make the substitution I suggested!What exactly is stopping you from doing that?
skipjack is offline  
May 27th, 2010, 03:31 AM   #7
Newbie
 
Joined: May 2010

Posts: 4
Thanks: 0

Re: Ellipse radius at specific angle?

So, what is stopping you for showing me how would you calculate it and what is the answer, you should clearly see that I'm not understanding any that you are saying.
keijojo is offline  
May 27th, 2010, 05:34 PM   #8
Global Moderator
 
Joined: Dec 2006

Posts: 20,469
Thanks: 2038

You originally asked to be told (in simple terms) how to calculate the radius, so I told you what to do. You didn't originally ask for the value that results from doing that calculation.

Without knowing what you are capable of understanding, I don't know how much detail to give. If you don't understand even a standard equation for an ellipse and you don't understand basic algebraic concepts, where should I start? I can't even refer you to any textbook, as you presumably wouldn't understand that either.
skipjack is offline  
May 15th, 2012, 12:08 PM   #9
Newbie
 
Joined: May 2012

Posts: 1
Thanks: 0

Re: Ellipse radius at specific angle?

I am trying to find the same formula and an example of it worked out with values. I am good at learning math once I see something worked out. While I work with trig and algebra functions daily, I am not a mathmatician and it has been twenty years since I last took a math class. If a non-condescending person who actually has the ability to work this problem out would do so showing the formula with the values plugged into the formula I would appreciate it.
vagabond is offline  
Reply

  My Math Forum > High School Math Forum > Algebra

Tags
angle, ellipse, radius, specific



Search tags for this page
Click on a term to search for related topics.
Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Find angle to specific point given random (x,y) coordinate olikkhhz Algebra 0 November 17th, 2013 06:45 AM
Radius angle from 2 points coderplus Algebra 9 August 4th, 2012 11:31 AM
radius of curvature of ellipse? two parts? Vesperlynd Calculus 2 July 21st, 2011 09:29 PM
Question dealing with a spiral shape with angle and radius i_am_cuul Algebra 1 April 23rd, 2010 08:50 PM
Solve angle and radius of oval pmoor Algebra 1 February 21st, 2009 04:55 PM





Copyright © 2019 My Math Forum. All rights reserved.