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Post by jasonh300
I have no concept of what 14% grade is. What is that in degrees? Or rise over run?

I've seen those signs before in eastern Tennessee between Chattanooga and Nashville, and also in Pennsylvania around Bethlehem. I know when the number's above 10, it's pretty friggin steep. I was also driving a moving van through Kentucky one time and couldn't maintain 30 MPH on the interstate on an incline.

Of course, I live in a place where you can park in neutral and not set the parking brake and your car will probably not move an inch.
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Post by jasonh300
fvwazing wrote:14% means the road drops 14m if you drive 100m. That is pretty steep.
What is that in feet? :lol: j/k

Yes, that's pretty steep. I did some research and the steepest grade on the U.S. Interstate system is 8%, and I have driven it (I-24/US-41/64 Westbound over Monteagle Mountain, TN).
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Post by jasonh300
mapcat wrote:What the hell are trucks doing on that road?!

Where is that? I want to make sure I avoid it.
I hope that it's just a picture of a truck, placed there to cast fear into the hearts of anyone who attempts to drive that road.
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Post by jasonh300
mapcat wrote:
jasonh300 wrote:I hope that it's just a picture of a truck, placed there to cast fear into the hearts of anyone who attempts to drive that road.
Sign says "Trucks use lower gear".
It works, doesn't it?
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Post by jasonh300
harling wrote:14% grade: arctan(0.14) = 8 deg.
27% grade: arctan(0.27) = 15 deg.
33% grade: arctan(0.33) = 18 deg.
So would 100% be 45 deg. or 90 deg.?
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Post by jasonh300
AlanOfTheBerg wrote:
jasonh300 wrote:So would 100% be 45 deg. or 90 deg.?
I imagine it would be 45deg where rise=run. Or run=fall. :o
Fall is right in that case. At that angle, I don't think anyone would be rising.
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Post by jasonh300
fvwazing wrote:1m down for 1m of road? 90 degrees, of course.

Edit:
Oops, my bad. Definition uses horizontal movement, not length of road.
Actually, you did say "length of road" (hypotenuse?) in your first post, but everything else involving pitch or grade is measured rise over run, so I suppose this would be too.

It's been 23 years since my last geometry class...
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Post by mapcat
What the hell are trucks doing on that road?!

Where is that? I want to make sure I avoid it.
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Post by mapcat
jasonh300 wrote:I hope that it's just a picture of a truck, placed there to cast fear into the hearts of anyone who attempts to drive that road.
Sign says "Trucks use lower gear".
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Post by mapcat
jasonh300 wrote:It works, doesn't it?
"Trucks TURN AROUND NOW" would work better.
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