Hey all, I was doing a physics question in preparation for an exam, but I cant seem to figure it out! The question: "Your favourite physics teacher who is late for class attempts to swing from the roof of a 24 metre high building to the bottom of an idential building using a 24 metre rope as shown. She starts for rest with the rope horizontal, but the rope will break if the tension force in it is twice the weight of the teacher. How high is the swinging physicist above level when the rope breaks?" http://img65.imageshack.us/img65/4771/physics27gc.jpg [Broken] What I tried was: Treat is as a centripetal force problem. Find the speed when T=2mg and W=mg. Once I find the speed, I can use conservation of energy to figure out what the height is. The problem is I dont know how to find speed! Any hints on how to figure out the Fnet when T=2mg and W=mg? Or am I doing this all wrong? Also, just to make sure, in the equation F=[m(v^2)]/r, F stands for Fnet, correct? If thats the case, then in the case of a rock attached to a string and being swung in a circle vertically: http://img217.imageshack.us/img217/5808/centripital8en.jpg [Broken] Then the net acceleration and force is not directed towards the centre anymore, correct?