physics!
posted by hannah! .
tarzan tries to cross a river by swinging from one bank to the other on a vine that is 10.0 meters long. his speed at the bottom of the swimg is 8.0 meters/second. Tarzan does not know that the vine has a breaking strnght of 1000 newtons. what is the largest mass that tarzan can have and still make it safely across the river?

Ac = v^2/r = 64/10 = 6.4 m/s^2
total tension = m (9.8+6.4) = 1000
m = 1000/(9.8+6.4) 
Rope tension at lowest point of swing
= M (g + a)
where
a = V^2/R
R = 10.0 m.
If it breaks,
m (g + V^2/R) = 1000 N
Solve for m. They tell you what v is. (It actually depends upon how high up he starts the jump) 
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