# How to find Vmax squared for circular motion?

Homework Statement:
Tarzan plans to cross a gorge by swinging in an arc from a hanging vine. if his arms are capable of exerting a force of 1500 N on the vine, what is the maximum speed he can tolerate at the lowest point of his swing? His mass is 80 kg, and the vine is 4.5 m long.
Relevant Equations:
Fmax= mvmax^2/r
T= m*vmax^2/r 1500 = (80kg)vmax^2/4.5

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Homework Statement:: Tarzan plans to cross a gorge by swinging in an arc from a hanging vine. if his arms are capable of exerting a force of 1500 N on the vine, what is the maximum speed he can tolerate at the lowest point of his swing? His mass is 80 kg, and the vine is 4.5 m long.
Relevant Equations:: Fmax= mvmax^2/r

T= m*vmax^2/r 1500 = (80kg)vmax^2/4.5
You forgot to consider Tarzans weight.

The mass is his weight.

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The mass is his weight.
No. It isn’t. Do a free body diagram of Tarzan at the base of the swing.

This is what the question gave me.

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This is what the question gave me.
We’ll, they should have stated local ##g## too, but you can assume 9.81 m/s².

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Think about Tarzan just hanging there with zero velocity. Does your equation make sense for ##v=0## in terms of the tension developed in his arms?

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The mass is his weight.