(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The water in a river flows uniformly at a constant speed of 2.50m/s between two parallel banks 80.0m apart. You are to deliver a package directly across the river, but you can only swim at 1.5m/s.

If you choose to minimize the distance downstream that the water carries you, in what direction should you head?

2. Relevant equations

x=x_o+v_xt

3. The attempt at a solution

Let's say the river is flowing towards the east and taking that as the x-axis, you must swim at some angle, x from the x-axis in the opposite direction of the flow of the river.

To have a minimum distance downstream, I figure that we must have zero displacement on the x-axis and a displacement of 80m on the y-axis.

So I came up with this right angled vector triangle with hypotenus 1.5(cos x)t and sides 80 and 2.5t. Using the Pythagoras theorem, I came up with

t = sqrt(6400/(2.25Cos^2 (x)-6.25))

but now i'm stuck! cos I think i'm conceptually flawed right from the start.

Please help! this question is driving me crazy!

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# Homework Help: Swimming vector problem

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