1. The problem statement, all variables and given/known data In a physics lab we were finding slope on semi-log graph paper, with the y (up) axis representing tension in Newtons, and the x (sideways) axis representing θ in radians. Sadly, the prof introduced the new concept of natural logs to me - I'd never heard of these until this day. He told us to use the natural logs of the y coordinates to find rise, and I have next to know idea what this means, other than pushing the ln button prior to inputting a number in my calculator. What I'm trying to find is not only how to do the natural logs, but also what unit my answer for slope will be in. Any help would be appreciated. 2. Relevant equations 3. The attempt at a solution If rise/run = y2 - y1/ x2 - x1, my equation looked like this: 5.00N - 9.67N/ 13∏/4 - 5∏4. This seems like complete nonsense to me.