Calculating Relative Velocity for Approaching Boats

AI Thread Summary
A boat is moving north at 5 m/s while another boat approaches from the southwest at 6 m/s. To find boat B's actual velocity, the relative velocity formula Vrel = Vb - Va is applied. A suggestion is made to redraw the velocity triangle to better visualize the angles, specifically using 135 degrees from the horizontal. This approach may clarify the calculation of the actual velocity of boat B. Understanding the vector components is crucial for solving the problem accurately.
ozbii
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Homework Statement


A boat is traveling due north at 5 m/s and a passenger on boat A sees another boat, boat b, approaching from south-west (45 degrees) at a speed of 6 m/s. What is boat B's actual velocity?

Homework Equations



Vrel = Vb - Va

The Attempt at a Solution


http://blob:https%3A//www.physicsforums.com/1c3c6810-6d14-4b51-8001-acb8be8f9167 http://blob:https%3A//www.physicsforums.com/0f6caecc-b8ad-4208-b8cb-c8fdd9c98d28
upload_2015-5-13_21-19-6.png
 

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Is there a question in there somewhere? (I can't see the first two images you posted)
 
ozbii said:

Homework Statement


A boat is traveling due north at 5 m/s and a passenger on boat A sees another boat, boat b, approaching from south-west (45 degrees) at a speed of 6 m/s. What is boat B's actual velocity?

Homework Equations



Vrel = Vb - Va

The Attempt at a Solution


http://blob:https%3A//www.physicsforums.com/1c3c6810-6d14-4b51-8001-acb8be8f9167 http://blob:https%3A//www.physicsforums.com/0f6caecc-b8ad-4208-b8cb-c8fdd9c98d28 View attachment 83441
Try redrawing your triangle a little differently so that the angle is 135 degrees from the horizontal. Imagine flipping your triangle upside down.
 
Hope this helps
 

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