Adding Vectors in Physics 1 to get the Net Displacement

AI Thread Summary
The discussion revolves around calculating the net displacement of a car that travels in multiple directions. The user attempted to solve the problem and calculated a total displacement of approximately 75.8 km and an angle of 32.4 degrees north of east. However, the correct answers are 74.05 km for the magnitude and 42.46 degrees north of east for the angle. The user expressed confusion about the discrepancy in the angle calculation despite being close on the magnitude. Clarification on the vector addition method and angle determination is needed to resolve the issue.
Wm_Davies
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Homework Statement



A car is driven east for a distance of 43 km, then north for 29 km, and then in a direction 29° east of north for 24 km. Determine (a) the magnitude (in km) of the car's total displacement from its starting point and (b) the angle (from east) of the car's total displacement measured from its starting direction.


The Attempt at a Solution



I do not know where I am going wrong, but I cannot get the answer no matter what I do.

I have attached a picture of the problem as I have worked it out.

For part (a) I have 75.8028368 km
for part (b) I have 32.4163299 degrees north of east

I am allowed a -/+7% tolerance.
 

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The answers are

(a) 74.054828934557 km


(b) 42.458201635351 ° north of east

I was fairly close on the magnitude, but I do not know why I am not getting the angle.
 
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