Vectors Question using Calculus -- Swimmer crossing a River

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Bob wants to swim across a 200 m wide river flowing west at 2.5 m/s, while he can swim at 4 m/s in still water. To reach a point directly opposite, he must angle his swim upstream to counteract the current. The discussion emphasizes the importance of drawing a vector diagram to visualize the relationship between Bob's swimming direction and the river's current. Ultimately, Bob's resultant velocity must be directed straight across the river, which requires calculating the appropriate angle and speed relative to the ground. Understanding these vector components is crucial for solving the problem effectively.
  • #31
ttpp1124 said:
Relative meaning in the direction of.

I know this is an old thread, but this just bothered me. Relative to does not mean 'in the direction of', relative to implies a subtraction i.e. 'from the perspective of'. A part of a vector in a certain direction is something different, i.e. a vector component / vector projection.
 

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