Jane, whose mass is 50.0 kg, needs to swing across a river (having width D) filled with person-eating crocodiles to save Tarzan from danger. She must swing into a wind exerting constant horizontal force , on a vine having length L and initially making an angle θ with the vertical (Fig. P8.81). Take D = 50.0 m, F = 110 N, L = 40.0 m, and θ = 50.0°.
(a) With what minimum speed must Jane begin her swing to just make it to the other side?
(b) Once the rescue is complete, Tarzan and Jane must swing back across the river. With what minimum speed must they begin their swing? Assume Tarzan has a mass of 80.0 kg.