the only way i see to derive that theta(angles between x and r) is with the angle I mentioned previously, but by subtracting it from 90deg. So theta =90-(θx/2rsin(θ/2)). I don't understand how to get it without the central angle
cos(theta) of Fg. Is there any way I could see a reference for this proof bc I feel like this convo is going to take a while with the responses. I can ask you about the reference too, but I feel like I'd learn much better with it.
I mistypes in the first post. it should be L = 2rsin(θ/2). I got the angle by finding the fraction of the total chord length x is, and then multiplying that with the central angle
force of gravity towards the center would be (r/R(radius of earth))*weight. Angle of Fg would be θx/2rsin(θ/2), so force parallel to chord would be w(r/R)*sin(θx/2rsin(θ/2)). Then plug in to f=ma
the forces would just be gravity(and normal force perpendicular to the chord) gravity would just be linear so (dist from center)/R * weight(at surface). To get an eq relating gravitational force towards the center with force parallel to the chord would require both time and dist which would have...