Hello, I hope this is a suitable forum, it's a million miles from homework but it may be on the same sort of level. A picture is worth a thousand words so please have a look at the attached picture. When the rope is pulled there isn't just the issue of gravity, but also of the friction of the rope over the metal bar. What I am wanting to calculate is the actual force that must be applied to stop the weight from falling, taking into account the friction. I really don't know where to start with this, but from the searching that I've done, this page seems to be using diagrams and words that seems applicable. http://www.engineeringtoolbox.com/bollard-force-d_1296.html The equation given is: S = F e-μα Where: S = effort force in the rope (N) F = load (N) e = 2.718 μ = friction coefficient (approximately 0.3 - 0.5 is common for a rope around a steel or cast iron bollard) α = angle where the rope is in contact with the bollard (radians) So, plugging in the following data (assuming the rope is only in contact with half the bollard): F = 300N e = 2.718 μ = 0.4 α = ∏ I get: 300 * ( 2.718 -0.4 * ∏ ) = 85.39 N Which seems to imply that the force that is needed to stop the weight from falling is 214.6 1N (300-85.39). However, I've got a feeling that I might be messing up the calculation, would somebody be kind enough to take a look for me? Thank you.