The vine has a fixed end, so Tarzan's path is circular. So the vine must not only support Tarzan's weight (or some component of it) but must also provide centripetal force to curve Tarzan's velocity. At Tarzan's lowest point, this can be expressed as:.

hello your question lacks some data attached below is the missing data

answer : T - mg = ma

Explanation:

Given that the vine has a fixed end and Tarzan's path is circular

At Tarzans lowest point the point can be expressed as shown below.

It can be expressed as : T - mg = ma

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