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rpullo
Nov5-09, 10:01 PM
1. The problem statement, all variables and given/known data

Tarzan wishes to swing across a crocodile infested river to consort with Jane, using a vine rope to swing on. In order to reach Jane's side he must swing so that the rope makes a maximum angle of 40 degrees to the vertical. Regarding Tarzan as an 85 kg point mass, what is the minimum breaking tension of the rope if the crocodiles are to be disappointed and Jane delighted?

(assume the rope is light and Jane loves Tarzan)

2. Relevant equations

Fg = mg (833 N)
Fc = T - Fg

3. The attempt at a solution

Don't know where to start..it's a bonus question for our test
Thanks!

rpullo
Nov5-09, 10:27 PM
An attempt at the question:

Fg is a constant 833 N on Tarzan.

Because Fc = T - Fg

T = Fc + Fg
= mv^2/r + 833
= 85v^2/r + 833

Sort of stuck there...

willem2
Nov6-09, 03:49 AM
Use conservation of energy to find v at the bottom of the swing. How high is tarzan above this point at the start of the swing?

rpullo
Nov7-09, 07:22 PM
That dosen't help me :(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:( :(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:( :(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:( :(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:( :(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:(:( :(:(:(