LAURA SANTOS

It was my understanding there would be no math.

J
----- Original Message -----
From: Marc R
To: obra@list.obra.org
Sent: Sunday, March 11, 2007 12:07 PM
Subject: [OBRA Chat] Measuring Hill Gradients Mathematically

(The hillclimb subject reminded me of this). When I teach algebra, I often tell my students that slope of a line is like grade of a road: slope is rise over run, and grade of a road is 5%, for example, if the road rises 5 ft for every 100 foot HORIZONTAL change (so grade = 5% and slope = 5/100 or .05). But in looking at some Tour de France numbers last summer I concluded that that was NOT how the grade of a climb there is measured. Can anyone explain their system? Is their 'grade' maybe the ratio of the vertical change to the actual change in distance of the rider -- i.e., the ratio of the vertical leg of the appropropriate right triangle to the HYPOTENUSE? Help! ;)
_______________________________________________
OBRA mailing list
obra@list.obra.org
http://list.obra.org/mailman/listinfo/obra
Unsubscribe: obra-unsubscribe@list.obra.org