Relative velocity of a canoe problem

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SUMMARY

The problem involves calculating the velocity of a canoe relative to a river, where the canoe's velocity is 0.470 m/s southeast and the river's velocity is 0.490 m/s east. The correct approach requires breaking down the velocities into their components. The east component of the canoe's velocity is calculated as 0.332 m/s, but the mistake arises in the subtraction of the river's velocity. The correct components must be derived using vector addition to find the canoe's velocity relative to the river.

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  • Understanding of vector addition and subtraction
  • Knowledge of trigonometric functions, specifically cosine
  • Familiarity with coordinate systems in physics
  • Ability to resolve velocities into components
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  • Learn how to resolve vectors into their components using trigonometry
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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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