Physics problem involving displacement of car

AI Thread Summary
The discussion revolves around solving a physics problem involving the displacement of a car driven in multiple directions. The first part of the problem, calculating the total displacement magnitude, was correctly solved as approximately 80.11 km. However, there was confusion regarding the angle of displacement, where an incorrect angle of 30° was initially used instead of the correct 33°. Participants emphasized the importance of using the right angle in calculations to obtain accurate results. The conversation highlights common challenges in physics problems related to vector components and angle measurements.
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Homework Statement



A car is driven east for a distance of 48 km, then north for 25 km, and then in a direction 33° east of north for 29 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.



Homework Equations


magnitude is sort of a^2+b^2
direction is tan theta = ay/ax


The Attempt at a Solution


I got part a right by finding magnitude of "R" which was sqrt of 62.5^2+50.11^2= 80.11 km i just can't seem to get part b right. i know it is north of east but whenever i do inverse tan of 50.11/62.5 i get 38.72 degrees which is wrong, HELP please
 
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welcome to pf!

hi wbetting! welcome to pf! :smile:
wbetting said:
I got part a right by finding magnitude of "R" which was sqrt of 62.5^2+50.11^2= 80.11 km …

no you didn't, you just got close

you used 30° instead of 33° ! :redface:
 
It marked it right on my online homework. Any idea how to do part b?
 
wbetting said:
It marked it right on my online homework.

but you used 30° instead of 33° ! :cry:
 
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