Will Tarzan safely cross the river?

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Tarzan, weighing 85 kg, attempts to swing across a river using a 10-meter vine while reaching a speed of 8.0 m/s at the bottom of his swing. The vine has a breaking strength of 1.0 x 10^3 N. To determine if he can safely cross, one must analyze the forces acting on him, particularly the tension in the vine and the centripetal force required for his circular motion. The net force at the bottom of the swing must equal the centripetal force, which includes the tension in the vine. Ultimately, calculations show that the tension exceeds the vine's breaking strength, indicating Tarzan cannot safely cross the river.
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Tarzan (m=85kg) tries to cross a river by swiming from 10.0m long vine. His speed at the bottom of the swing, just as he clears the water, is 8.0m/s. Tarzan doesn't know that the vine has a breaking strength of 1.0*10^3 N. Does he make it safely across the river?

mass= 85kg
rope= 10m
velocity= 8.0m/s
Tension= 1.0*10^3N
and it has to do with this equation somehow

Fc(force that maintains circular motion)
mass (m)
Vt^2 (tangential speed)^2
r (distance to axis)
w (angular speed)

Fc=m*((Vt^2)/r) or Fc=m*r*(w)^2

I know the answer is no but i don't know how to get there :cry:
well thanks again o:)
 
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Think about all the forces acting on Tarzan at the bottoom of his swing. The net force must equal the centripetal force. Some of that total foce is the tension in the vine.
 
Hmmm... This looks familiar.
Try analysing all the forces acting on Tarzan. With quite a number of assumptions you will find there is only 2. Then find the point where the Tension is maximum.

Centripetal force is the net force of the 2 forces. This is actually almost like a pulley question.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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