Calculating Relative Velocity for Approaching Boats

[ozbii]

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

 

[phinds]

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

 

[lion_]

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.

 

[lion_]

Hope this helps