Relative velocity of a canoe problem

AI Thread Summary
The problem involves calculating the velocity of a canoe relative to a river, given its velocity relative to the earth. The canoe moves at 0.470 m/s southeast, while the river flows at 0.490 m/s east. The initial attempt to find the east component of the canoe's velocity was incorrect, leading to a misunderstanding of the vector components. The correct approach involves breaking down the velocities into their respective components and solving for the canoe's velocity relative to the river using vector addition. The discussion emphasizes the importance of accurately calculating the components to arrive at the correct magnitude of the velocity.
LadyW
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Homework Statement



A canoe has a velocity of 0.470m/s southeast relative to the earth. The canoe is on a river that is flowing at 0.490 m/s east relative to the earth.Find the magnitude of the velocity Vc/r of the canoe relative to the river. there is a graph: Vr/e pointed directly on the x-axis to the right (positive) and Vc/e pointed 45 degrees down between x positive and y negative axis.


Homework Equations






The Attempt at a Solution


I found the east component first;
V=V0*cos 45=0.47*cos45=0.332m/s
V cr=V-Vcriver=0.332m/s-0.490m/s=-0.158 since we need magnitude it's 0.158, however the answer is wrong. Could you please point out my mistakes? Thank you!
 
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You can make a guess to get things started. If the river runs to the east at .5 m/s and you paddle your canoe to the south at .5 m/s you will end traveling south east at √2 * .5 m/s

We have the right direction but we are moving faster then stated in the problem. What you need is

.47 i + x i = .49 * cos45 i

0 j + y j = -.49 * cos45 j

Solve for x and y. They will be the components of the velocity relative to the river.
 
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