
Algebra PreAlgebra and Basic Algebra Math Forum 
 LinkBack  Thread Tools  Display Modes 
October 31st, 2009, 07:56 AM  #1 
Newbie Joined: Oct 2009 Posts: 4 Thanks: 0  Deflection Angle of Closed Traverse: Traverse Theory
How do I calculate the deflection angle at B? The deflection at angle B is basically the line AB extended past B, and the angle created by B,B',C if that makes sense. [attachment=1:2j71u0mv]Traverse Theory.JPG[/attachment:2j71u0mv] [attachment=0:2j71u0mv]TT Cleared.JPG[/attachment:2j71u0mv] 
October 31st, 2009, 08:22 AM  #2 
Global Moderator Joined: Dec 2006 Posts: 19,285 Thanks: 1681 
2. Interior angle at B = 42°36' + 64°56' = 107°32'. Since it's an interior angle, not a deflection angle, the left/right question doesn't make sense. 1. Your definition of deflection angle builds in "clockwise" (i.e., "right"), rather than anticlockwise, whenever the vertices are alphabetically ordered clockwise (at least when the polygon is convex). The deflection angle at B = 180°  107°32' = 72°28'. 3. Bearing of CD is S64°56'E  38°16' = S26°40'E. 4. Can you do this final part? (Check the meaning of "azimuth" if you don't already know it.) 
October 31st, 2009, 11:56 AM  #3 
Newbie Joined: Oct 2009 Posts: 4 Thanks: 0  Re: Deflection Angle of Closed Traverse: Traverse Theory
Ok, so in a clockwise approach: Az AB= 42°36' +180° Az BA= 222°36' ?B 107°32' Az BC= 115°04' +180° Az CB= 295°04' ?C 143°44' Az CD= 151°20' +180° Az DC= 331°20' ?D 38°16' Az DA= 293°04' 180° Az AD= 113°04' What am I doing wrong? 
October 31st, 2009, 01:19 PM  #4 
Global Moderator Joined: Dec 2006 Posts: 19,285 Thanks: 1681 
What the . . . ? The line is already annotated N70°42'W. Just subtract that angle from 360° to get the angle clockwise from due North, i.e., 289°18'.

October 31st, 2009, 01:40 PM  #5 
Newbie Joined: Oct 2009 Posts: 4 Thanks: 0  Re: Deflection Angle of Closed Traverse: Traverse Theory
OH I think I see now, so would this be TRUE of azimuth and bearing relation: N.E. Quadrant: Bearing = Azimuth S.E. Quadrant: 180°  Azimuth = Bearing AND 180°  Bearing = Azimuth S.W. Quadrant: Azimuth  180° = Bearing AND 180° + Bearing = Azimuth N.W. Quadrant: 360°  Azimuth = Bearing AND 360°  Bearing = Azimuth I tried to calculate it by going through the entire process, but should I not have produced the same answer anyway? 
October 31st, 2009, 02:42 PM  #6 
Global Moderator Joined: Dec 2006 Posts: 19,285 Thanks: 1681 
S.W. Quadrant: Azimuth  180° = Bearing AND 180° + Bearing = Azimuth is what you probably intended. Now you should be able to spot the errors you made earlier. 
October 31st, 2009, 02:53 PM  #7 
Newbie Joined: Oct 2009 Posts: 4 Thanks: 0  Re: Deflection Angle of Closed Traverse: Traverse Theory
Will do. Thanks you've been an awesome amount of help.


Tags 
angle, closed, deflection, theory, traverse 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Calculating angle sin and sin angle without any functions.  Gyiove  Algebra  1  February 26th, 2014 04:57 PM 
prove Angle DFE=3 Angle AEF  Albert.Teng  Algebra  26  February 19th, 2013 06:21 PM 
Closed set and closed ball  Vasily  Real Analysis  3  February 4th, 2013 12:49 PM 
Is the union of infinite disjoint closed sets closed?  03sqq  Real Analysis  4  November 13th, 2012 03:40 AM 
computing a closed traverse using bearings...  dusty388  Algebra  2  December 5th, 2011 06:09 PM 