How Do Canoeists' Velocities Reveal Water Speed and Their Effort?

AI Thread Summary
The discussion focuses on determining the speed of water relative to shore and the speed of two canoeists paddling in opposite directions. One canoeist moves upstream at -1.2 m/s, while the other moves downstream at +2.9 m/s. To find the water speed, the velocities of both canoes must be considered, as they exert the same effort and maintain equal speed relative to the water. The problem requires calculations based on the given velocities to derive the water speed and each canoe's speed relative to the water. The thread emphasizes the need for analytical approaches to solve the problem.
svayl
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Ok, I can not get the answer to this question!

Two canoeists in identical canoes exert the same effort paddling and hence maintain the same speed relative to the water. One paddles directly upstream (and moves upstream), whereas the other paddles directly downstream. With downstream as the positive direction, an observer on shore determines the velocities of the two canoes to be -1.2 m/s and +2.9 m/s, respectively.

(a) What is the speed of the water relative to shore?
m/s
(b) What is the speed of each canoe relative to the water?
canoe going upstream m/s
canoe going downstream m/s
 
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svayl said:
Ok, I can not get the answer to this question!

Two canoeists in identical canoes exert the same effort paddling and hence maintain the same speed relative to the water. One paddles directly upstream (and moves upstream), whereas the other paddles directly downstream. With downstream as the positive direction, an observer on shore determines the velocities of the two canoes to be -1.2 m/s and +2.9 m/s, respectively.

(a) What is the speed of the water relative to shore?
m/s
(b) What is the speed of each canoe relative to the water?
canoe going upstream m/s
canoe going downstream m/s

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