River Crossing: Solving for Time with Jon's Boat Speed and River Current

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To determine how long it takes Jon to row across a 300m wide river with a current of 6m/s while rowing at 4m/s, one must consider the relative motion of the boat and the river. The effective speed of Jon's boat across the river depends on the angle he rows against the current. The equation for time is t = d/v, where d is the distance across the river and v is the effective speed. Understanding the reference frames is crucial, as Jon's movement is affected by both his rowing speed and the river's current. The direction of rowing significantly impacts the time taken to cross.
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if jon rows a boat at 4m/s the river is moving at 6m/s and the river is 300m how long does it take to row across. I need the equation
 
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cubs1908 said:
if jon rows a boat at 4m/s the river is moving at 6m/s and the river is 300m how long does it take to row across. I need the equation

think about the reference frames. if you're standing aside, how fast is the river moving? how fast is the boat moving? which is moving faster, slower?

think about it from jon's point of view. if he does no work, how fast is he moving? how fast are you moving if he is observing you? he is doing work, so how is he moving in comparison to you and the river?

hopefully that helps
 
Rather then trying to find the equation, i suggest you try to understand what's happening in the problem. First of all, what is jons goal? What factors influence how this happens?
 
this question can change drastically with the direction of the rower and river. Are they in the same direction? Are the forces perpendicular?

t=d/v
 
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thanks alot
 
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