How Can Vernie and George Swing Across the River Despite the Wind?

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Vernie needs to swing across a 50m river to rescue George, facing a wind force of 110N. To determine the minimum speed for Vernie to reach the other side, the energy balance equation must account for both kinetic and potential energy, as well as the work done against the wind. The relevant equations include kinetic energy (KE = 1/2mv²) and potential energy (PE = mgh). A diagram is suggested to clarify the vine's position relative to the river. The discussion emphasizes the importance of including wind resistance in the calculations for both Vernie's initial swing and the return trip with George.
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Homework Statement


Vernie (mass of 50.0kg) needs to swing across a river to rescue George (mass of 80kg). She must swing into a constant horizontal wind force F ona vine that is initially at an angle of O with the verticle. The width of the river between them is 50.0m. The force of the wind blowing towards Vernie is 110N, and the length of the rope os 40.0m an dthe angle is 50 degrees.
(a.)With what minimum speed must Venie begin her swing in order to just make to the other side.
(b.) Once the rescue is complete, George and Vernie must swing back across the river, with what minimum speed must they begin their swing?


2. L-(Lcos50 deg)
KE(Kinetic Energy)=1/2mv2

PE(Potential Energy)=mgh




The Attempt at a Solution


KE=PE
1/2mv2=mgh

V= sqrt 2gh
 
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A diagram would be helpful. (Where is the vine with respect to the river?)

In setting up your energy balance equation, don't forget to include the work that must be done against the wind force.
 
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