What Is the Person's Resultant Displacement After the Walk?

AI Thread Summary
The discussion revolves around calculating the resultant displacement of a person after a walk involving four vectors. The angle of the resultant displacement has been correctly identified as 238.08 degrees, but the magnitude calculation of 216.45 m is incorrect. The user suspects an error in the angle of the fourth vector, suggesting it should be 119 degrees instead of 115 degrees. The conversation also touches on how to mark the question as solved after receiving help. Accurate calculations of vector components are crucial for determining the correct resultant displacement.
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Homework Statement



A person going for a walk follows the path shown in the figure, where y1 = 290 m and θ = 61.0°. The total trip consists of four straight-line paths. At the end of the walk, what is the person's resultant displacement measured from the starting point?

____ m? ____ degrees? (from the + x axis)

Homework Equations



http://img257.imageshack.us/img257/3813/physicsho5.th.jpg

The Attempt at a Solution



I've calculated and found the correct angle, which is 238.08 degrees but I don't know why I keep getting the wrong magnitude. I got 216.45 m and it's incorrect.

here is my work:

vector A = 100N @ 0 degrees ; A_x = 100 A_y = 0
vector B = 290N @ 270 degrees; B_x = 0 B_y = -290
vector C = 150N @ 210 degrees; C_x = -129.90 C_y = -75
vector D = 200N @ 115 degrees; D_x = -84.52 D_y = 181.26
____________________________________________________
F_x = -114.42; F_y = -183.74

tan^-1 (-183.74/-114.42) = 58.1 degrees + 180 degrees = 238.08 degrees

so for the magnitude I did

-114.42^2 + -183.74^2 = c^2
sq root of 46852.3 ... or 216.454 = c

but that is wrong, can anyone tell me what c would be? thanks.
 

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sorry, I've attached the picture.

The first vector is vector B in my solutions.
 
Ok, I"ve got the pic. The only problem I see is the value of the angle of the 4th vector. You have 115deg, I get 119deg.
 
thank youuuu! how do I mark this as solved now?
 
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