I'm just wondering about using a Mohr's Circle, do I need to use the same scale for the x and y axes, as surely otherwise my choice of scale greatly impacts the results. I am using one to get my principle second moment of areas, Ix and Iy, for an equal L section. Ix and Iy are where the Mohr's circle cross the x axis, but depending on my scale this can vary hugely! I'm just wondering if anyone has any advice? Thanks! Note: This is when the two points on my Mohr's circle have the same value on the x-axis, so when I join them up I have a vertical line.