Quandaries and Queries


dWho is asking: Parent
Level: Secondary

The gradiant of a hill is 9%. What angle is created by the run/rise of the hill and 0 degrees?



Hi Jim,

If the gradient is 9% = 9/100 then the rise over the run is 9 over 100.

If t is the angle created by the hill and 0 degrees as in the diagram then

tan(t) = 9/100 = 0.09


t = tan-1(0.09)



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