I'm taking a Geodesy refresher course and was wondering if anyone out there can point me in the right direction. Thanks in advance!
Setup on station ÛÏAÛ (elevation 1000.00Ûª) with a HI of 5.55Ûª, you measure a zenith angle 97å¼00Ûª15Û to a plumbed rod on station ÛÏBÛ to a rod reading of 5.55Ûª, and the slope distance is 300.00Ûª to the rod reading. What is the elevation of station ÛÏBÛ
1000 + 5.55 + sin(7d00'15") * 300 - 5.55
Thanks Tommy!
Isn't "B" lower than "A"?
MathTeacher, post: 395234, member: 7674 wrote: Isn't "B" lower than "A"?
Yes it is. It should be subtracted.
Use "+" and use the cos(97å¡00'15"). It will automatically make it negative. I prefer using the angles as their read, and using cosine instead of subtracting "90" and thinking about if I should add or subtract. What if it was a zenith of 83å¡? You would have to subtract that zenith from 90 just to get the number you want to take the sine of.
If you do want to use the "vertical" angle instead of the zenith, subtract the zenith from 90. then it's the right sign (pos or neg)
If you use cos(97d00'15") you can always add and the cosine takes care of the +/-sign for you.
Edit: Tom beat me to it. I need to quit fetching multiple threads so it takes a while to get around to reading some.
But I wonder if they want a more detailed answer. First off, how about accounting for refraction of the air and curvature of the earth?
Then at 300 ft it isn't going to make a huge difference, but if you string a lot of measurements together to cover large distacnes, you will need to get into orthometric correction, which is where the geodesy comes in.
