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

[svayl]

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

 

[LowlyPion]

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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What have you tried?

 

[baba89]

I would first clarify the question by asking for additional information such as the direction and magnitude of the current, the distance between the canoes, and the time at which the velocities were measured. Without this information, it is difficult to accurately answer the question. However, based on the information provided, I can make some assumptions and provide a general response.

(a) The speed of the water relative to the shore can be calculated using the formula: speed of water = speed of canoe going upstream + speed of canoe going downstream. In this case, the speed of the water would be 1.7 m/s.

(b) The speed of each canoe relative to the water can be calculated by subtracting the speed of the water from the observed velocities. Therefore, the canoe going upstream would have a speed of 2.9 m/s relative to the water, and the canoe going downstream would have a speed of 4.6 m/s relative to the water.