Vector Question: Swimmer Across River Diagram Help

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To solve the vector problem of a swimmer crossing a river, it's essential to visualize the scenario using a right triangle diagram. The river flows at 7 km/h horizontally, while the swimmer's speed relative to the water is 8 km/h at an angle. By drawing the triangle of velocities, one can determine the swimmer's effective speed directly across the river. Understanding the components of the swimmer's velocity helps clarify the true course across the river. Properly representing these vectors is crucial for solving related questions effectively.
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Homework Statement


A swimmer heads across a river flowing at 7km/h.
Her speed relative to the water is 8km/h.
The river is 362m wide.
There are other questions; however, I just need help with the diagram.

Homework Equations





The Attempt at a Solution


I'm not too sure on how to draw the diagram- I made a right angle triangle with the bank as shown in the picture. Is this correct?
 

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Not quite.

The river is flowing (right) at 7km/hr
The swimmer moves (diagonally) at 8km/hr

So you can calculate how fast the swimmer is moving directly across the river by drawing a triangle of velocities.

Once you've got the speed it's easy.
 
Oh I see what you mean, i wasn't sure if relative to implied it was the true course. Thank you.
 

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