Final answer:
In canoeing, when stroking the oar, most of the force should be applied at the beginning of the stroke, where the oar blade is vertical and fully submerged to efficiently leverage the water's resistance. Staying close to the shore when paddling upstream minimizes resistance against the canoe, and staying near the middle of the stream maximizes the assisting force of the water when going downstream.
Step-by-step explanation:
Understanding Canoeing and Force Application
When canoeing, it is essential to understand how and where to apply force to efficiently maneuver the canoe with the oars. While paddling a canoe upstream, the best practice is to stay as close to the shore as possible to minimize the force pushing against the canoe. This is due to the fact that water near the shore flows more slowly because of the resistance created between the shoreline and water, and between adjacent layers of water that cause turbulence. Conversely, when canoeing downstream, it is advantageous to stay near the middle of the stream where the water moves faster and can help increase the canoe's velocity, thus requiring less effort from the paddler.
In terms of specifically where to apply the most force when stroking the oar, the answer lies in the mechanics of how boats move through the water. The force that propels a boat forward comes from the interaction between the oars and the water. When a rower pulls the oar through the water, they should apply the most force at the beginning of the stroke when the oar blade is fully submerged and vertical in the water. This is because it allows the rower to utilize the resistance of the water effectively to push the canoe forward.