Find the velocity of the swimmer relative to the shore

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AI Thread Summary
The discussion focuses on calculating the swimmer's velocity relative to the shore, given their speed and direction, as well as the current's influence. The swimmer moves at 5 mph at 30 degrees south of east, while the current flows at 1.5 mph at 30 degrees west of north. The equation Vsl = Vsw + Vwl is highlighted as essential for solving the problem, where Vsw is the swimmer's velocity relative to the water, Vwl is the water's velocity relative to the land, and Vsl is the swimmer's velocity relative to the land. Participants emphasize the importance of showing work in homework discussions to facilitate better assistance. The conversation indicates a struggle with setting up the problem and finding the correct velocities.
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Homework Statement


A swimmer is moving 30 degrees south of east at a constant speed of 5mph relative to the water. A current is flowing 30 degrees west of north at a constant speed of 1.5mph.

Find the velocity of the swimmer relative to the shore. After 2 hours, what is the swimmers displacement? How FAR is the swimmer from his target position if he swam unaware of the current?

Homework Equations


Vsl = Vsw + Vwl
Vox = Vo(cos30)
Voy = Vo(sin30)

The Attempt at a Solution


Vox = 5cos30 = 4.33
Voy = 5sin30 = 2.5
 
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Surely you must have some idea?
 
CompuChip said:
Surely you must have some idea?

I wouldn't have asked if I knew...
 
Hehe, obviously I didn't expect you to say "yes, I know the answer already, I just want to check if you know it".
But when asking questions about homework, we would like you to show some work which you have already tried, even if you think it is leading you nowhere.

Does an equation like
vSW + vWL = vSL
sound familiar,
where vSW is the velocity vector of the swimmer relative to the water, vWL of the water relative to the land, and vSL of the swimmer relative to the land
 
CompuChip said:
Hehe, obviously I didn't expect you to say "yes, I know the answer already, I just want to check if you know it".
But when asking questions about homework, we would like you to show some work which you have already tried, even if you think it is leading you nowhere.

Does an equation like
vSW + vWL = vSL
sound familiar,
where vSW is the velocity vector of the swimmer relative to the water, vWL of the water relative to the land, and vSL of the swimmer relative to the land

Yes, it does look familiar. I just have hard time setting it up. The problem I have now it finding the velocities. I believe the equations I presented are correct?
 
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