I'm a high school student who hasn't had the pleasure of taking physics yet, so forgive me if the answer is obvious. The problem I have involves an earth anchor drilled vertically into the earth.
I am trying to figure out the equation that would give the highest amount of permissible force uniformly distributed on the exposed top part before the anchor would rotate. Just a force perpendicular to the vertical auger. What I mean by rotate is that it would pivot at a point halfway down the auger, like a lever with a fulcrum in the middle (x axis), and not unscrew itself from the earth (z axis). Of course this would be easy if it were in air, but I'm lost at how to calculate it in dirt. I came here from Physics Stack Exchange. The auger would be 9 inches long and immersed in 1.52 g/cm consistently dry soil. Any help would be greatly appreciated.