This problem seems simple, but I can't get the answer: 1. The problem statement, all variables and given/known data Tarzan tries to cross a river by swinging from one bank to the other on a vine that is 10.0 m long. His speed at the bottom of the swing is 8.0 m/s. Tarzan does not know that the vine has a breaking strength of 1000 N. What is the largest mass that Tarzan can have and still make it safely across the river. 2. Relevant equations Fc=(m*v2)/(r) 3. The attempt at a solution 1000 N=(m*(8 m/s)2)/(10 m) The answer is apparently 62 kg, and what I'm getting is over double that, so I'm obviously doing something wrong. I'm really not sure what I'm missing.