How Can a Swimmer Land Directly Across a River with a Current?

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SUMMARY

The swimmer achieves a speed of 0.75 m/s in still water and swims across a river that is 72 m wide, landing 54 m downstream. The speed of the river current is calculated to be 0.5 m/s, and the swimmer's velocity relative to the shore is 0.94 m/s. To land directly across from the starting position, the swimmer must aim at an angle that compensates for the current, requiring the use of trigonometric principles to determine the correct direction.

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  • Understanding of basic physics concepts, specifically relative velocity.
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  • Familiarity with vector addition and decomposition.
  • Ability to solve problems involving motion in two dimensions.
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  • Study vector addition in physics to understand how to combine velocities.
  • Learn about the sine and cosine rules in trigonometry for solving triangles.
  • Explore relative motion concepts in fluid dynamics.
  • Practice similar problems involving swimmers or objects moving in currents.
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I really need help with this question

A swimmer who achieves a speed of 0.75 m/s in still water swims directly across a river 72 m wide. The swimmer lands on the far shore at a position 54 m down stream from the starting point.
a)Determine the speed of the river current.
b)Determine the swimmer's velocity relative to the shore.
c)Determine the direction the swimmer would have to aim to land directly across from the starting position.

I did (a) and (b).
For (a) i got 0.5 m/s
For (b) i got 0.94 m/s

I have no idea what so ever how to do (c). Can anyone please atleast help me with this one??
 
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Make this problem into a triangle and try inverting the angle.
 

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