Can someone help me on a Relative Motion physics Question?

AI Thread Summary
The discussion revolves around a physics problem involving a river flowing east to west at 3.0 m/s and a boat that can move at 4.0 m/s across it. The first part of the question asks for the time taken to cross the river when the boat is pointed directly north, resulting in a downstream drift due to the river's current. The second part requires calculating the crossing time when the boat is angled upstream to counteract the current. Participants are also prompted to discuss the relevant vector equations used in relative motion problems, which include terms like Va and Va rel b. Understanding these concepts is crucial for solving the problem effectively.
azngirl92
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A river flows east to west at 3.0 m/s and is 80 m wide. A boat, capable of moving at 4.0 m/s, crosses in two different ways.
(a) Find the time to cross if the boat is pointed directly north and moves at an angle downstream.
(b) Find the time to cross if the boat is pointed at an angle upstream
 
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What is the vector equation you have been learning about for use in all of these relative motion exercises? It involves terms such as Va and Va rel b, etc.
 

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