Trouble with basic Vector Addition Problem

AI Thread Summary
The discussion revolves around calculating the total displacement for a treasure hunt involving vector addition. The problem includes movements of 5 paces North, 3 paces East, and 4 paces Southeast, with each pace measuring 0.750 m. The confusion arises in determining the components of the Southeast vector, specifically why its length is 2.12 m instead of 3.00 m. It is clarified that since the Southeast direction creates a 45-degree angle, the components can be calculated using sine and cosine functions, leading to the correct values for Cx and Cy. Understanding the relationship between the components helps clarify the overall displacement calculation.
ERoday
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This a book example that I have the answer to but do not understand.
What are the magnitude and direction of the total displacement for the treasure hunt? The instructions to find the treasure are 5 paces North, 3 paces East, then 4 paces Southeast. Each pace is 0.750 m in length.

So I understand that to find the total displacement you need to find the components of each vector. So 5 pace North = vector [A] which would be Ax= 0 and Ay= 3.75m, and 3 paces east =vector which would be Bx= 2.25m and By= 0 but for 4 paces southeast the book gives the answer to be Cx=2.12 and Cy =-2.12 and I understand why those components are positive and negative but not why the distance is 2.12. Why isn't it Cx=3.00m and Cy= -3.00m?
 
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What would the length of the vector C be if Cx and Cy were both 3.00 m?
 
[4.24m] so bad logic on my part but I still don't understand how to find vector [C]
 
I hope you understand the problem easier from a drawing. All length are in paces. Find the x, y components of the red vector (in paces) first.

ehild.
 

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You want the length of C to be 3.00 m. Since you're going southeast, you know that Cy = -Cx. Put those two statements together to solve for Cx and Cy.
 
I understand it better now. Thanks. I see that vector [C] is a hypotenuse type angle (forgive my serious lack of physics jargon) so I can look at the intersection and see that the angle is 45 degrees and use sine and cosine to find Cx and Cy. I just thought there was a simpler way to do it. Like for vectors [A] and I just looked at the positive and negative positions to find the components.
 
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