- #1

opus

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## Homework Statement

You wish to row straight across a 63 meter-wide river. You can row at a steady 1.3 m/s relative to the water and the river flows at 0.57 m/s.

In what direction should you head, and how long would it take you to cross the river?

## Homework Equations

## The Attempt at a Solution

I've attached an image to show my drawing of the situation.

What I have done is make 3 vectors.

##\vec v## represents the boat's vector and it's unit notation is ##\vec v = (0\hat i + 1.3\hat j)##

##\vec u## represents the current of the river with ##\vec u =(0.57 \hat i + 0\hat j)##

##\vec T## represents the sum vector and I get ##\vec T =(0.57 \hat i + 1.3\hat j)## ##=(1.42~m/s,66.3°)##

Now I'm not sure where to go after this. I know the current will be pushing the boat in a manner that causes it to not be perpendicular to the shore and I need to find and angle to aim the boat so that it can get straight across.

The problem mentions the term "relative" so I kind of think of reference frames, but I'm not sure how to go about using such a thing here.