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## Homework Statement

Tarzan has a mass of 80 kg. Starting from rest. He swings over a river, on a vine of length 4m long. However, the vine will break if its tension exceeds 100 N. Will the vine break?

## Homework Equations

(total) F=ma ... (in both directions?)

Newton's second law.

W=FD=mgh(final)-mgh(intial)

## The Attempt at a Solution

At first I thought to find the acceleration using newton's second law( Tmax=100N, m=80kg, g=9.81 m/s^2. I used the formula T-mg=ma and got an acceleration of 2.69.

...I then thought to use the formula for work and got 3139.2 J (80kg*9.81m/s^2*4m)

I'm just completely stuck at this point. It seems like I need to find velocity but I can't come up with a good answer. I also thought to maybe find the tension used, but I can't seem to find an answer that way ether. I've also tried finding the weight that the max force can handle but that doesn't work for me. I just seem to be going in circles. I think this is simple i'm just forgetting something.

SOLUTION UPDATE?

I just had an idea. since I used W=mgh (3139.2 J) ... can I use W=fd (all in the y direction) so W=(T-mg)(4m) ... (3139.2J / 4m) + (80kg*9.81m/s^2) ... (W/m) + mg = T .... T=1569.6 N COuld that be the answer? resulting in the rope breaking?

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