Climbing grade
06-03-07, 08:45 AM
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Climbing grade
I have Google map and I found the hill I ride. How do I work out the % grade 
06-03-07, 10:29 AM
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Short version: Grade = (Change in vertical)/(Change in Horizontal)
Long version: https://en.wikipedia.org/wiki/Grade_%28slope%29
Long version: https://en.wikipedia.org/wiki/Grade_%28slope%29
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06-04-07, 09:11 AM
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Sorry, Google earth. So I found my hill. Bottom of hill is 775ft and the top is 807. The distance is 935 ft. How do I work out the %
Thanks
Thanks
06-04-07, 09:18 AM
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vert: 807 - 775 = 32 feet
horz: 935 ft
grade = vert/horz: 32 / 935 = .034 = 3.4% grade
edited - to change architectural terms to something more conventional.
horz: 935 ft
grade = vert/horz: 32 / 935 = .034 = 3.4% grade
edited - to change architectural terms to something more conventional.
06-04-07, 09:19 AM
#6
----
Originally Posted by cc_rider
rise: 807 - 775 = 32 feet
run: 935 ft
grade = rise/run: 32 / 935 = .034 = 3.4% grade
run: 935 ft
grade = rise/run: 32 / 935 = .034 = 3.4% grade
bingo!
06-04-07, 09:30 AM
#7
Making a kilometer blurry
Easy way out: find the hill at https://www.toporoute.com and map just the hill. Click "Elevation" and read the stats at the top.
Be careful with short (<100ft) sections, as it seems the data are not suitable for accuracy at that level.
One note on Google Earth is that the distance measured is path distance, not horizontal distance. So, it's measuring the hypotenuse, and you want the base of the triangle. If you change the exaggeration, you will see the distance change. At 3.4%, the difference is small, but as you get steeper, this starts to have a bigger impact.
Be careful with short (<100ft) sections, as it seems the data are not suitable for accuracy at that level.
One note on Google Earth is that the distance measured is path distance, not horizontal distance. So, it's measuring the hypotenuse, and you want the base of the triangle. If you change the exaggeration, you will see the distance change. At 3.4%, the difference is small, but as you get steeper, this starts to have a bigger impact.
06-04-07, 09:33 AM
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Originally Posted by waterrockets
One note on Google Earth is that the distance measured is path distance, not horizontal distance. So, it's measuring the hypotenuse, and you want the base of the triangle. If you change the exaggeration, you will see the distance change. At 3.4%, the difference is small, but as you get steeper, this starts to have a bigger impact.
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06-04-07, 10:15 AM
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Originally Posted by bdcheung
A point also covered in my cited Wiki article. Indeed, there is a difference between the tangent angle measurement and the cosine.
