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danielatha4
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Homework Statement
Two twins set out to row separately across a swiftly moving river. They have identical canoes, and can row at the same speed in still water. Twin A aims straight across the river but, due to the current, is carried downstream before reaching the opposite bank. Twin B aims her canoe upstream at an angle of 56.0 degrees relative to the riverbank, so as to arrive on the opposite side at a point that is directly across from her starting point.
Calculate the ratio of the time it takes twin A to cross the river to the time it takes twin B to cross.
Determine the direction of twin A's motion, expressed as an angle relative to the downstream direction.
Homework Equations
The Attempt at a Solution
In order to find a ratio of time, I set up update of position formulas.
Twin A:
[tex]\Delta[/tex]X=Vavg*t
In the case of the x direction I'll call the initial velocity V which should equal Twin B's initial velocity
[tex]\Delta[/tex]X=V*t
time for twin A:
t=[tex]\Delta[/tex]X/V
Twin B:
[tex]\Delta[/tex]X=Vcos34*t
t=[tex]\Delta[/tex]X/Vcos34
Ratio of A/B for t is cos34, I got this part right.
I don't know how to go about the second part. The drag of the water represents a Force vector, and Twin A start off with a velocity vector in the x direction.
What I do know:
Initial y position=0
Initial y velocity=0