Is There More Than One Way to Solve a Trivial Vector Problem?

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The discussion centers on differing solutions to a vector problem, where one participant arrived at the answer 6.7i + 16j, while another calculated 16i + 6.7j. Both answers stem from different interpretations of vector components based on direction. The consensus is that the original solution presented in the attached image is incorrect, as the correct method involves using cosine for the x-component and sine for the y-component of the vectors. Ultimately, clarity on how to relate the i and j components to compass directions is crucial for solving such physics problems accurately.
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Homework Statement
Graphically determine the resultant of the following three vector displacements: (1) 24 M, 36 degrees north of east; (2) 18 m, 37 degrees east of north; and (3) 26 m, 33 degrees west of south.
Relevant Equations
Vy=Vsintheta
Vx=VCostheta
I got the attached photo from someone who solves physics problems on youtube. As you can see their final answer is 6.7i+16j. I understand how she got these values but I came out with something slightly different. I solved for the x and y components on the opposite side of each vector. So basically I came out with 16i+6.7j. Both answers make sense but I believe it comes down to a matter of perspective.

I searched around on the internet and I see that many people took different approaches to this problem resulting in people either getting my answer or the attached answer.

Are they both technically right? It feels as though that a lot of these physics problems come down to a matter of perspective.
 

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  • Screen Shot 2021-01-29 at 3.09.31 PM.png
    Screen Shot 2021-01-29 at 3.09.31 PM.png
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quittingthecult said:
Homework Statement:: Graphically determine the resultant of the following three vector displacements: (1) 24 M, 36 degrees north of east; (2) 18 m, 37 degrees east of north; and (3) 26 m, 33 degrees west of south.
Relevant Equations:: Vy=Vsintheta
Vx=VCostheta

I got the attached photo from someone who solves physics problems on youtube. As you can see their final answer is 6.7i+16j. I understand how she got these values but I came out with something slightly different. I solved for the x and y components on the opposite side of each vector. So basically I came out with 16i+6.7j. Both answers make sense but I believe it comes down to a matter of perspective.

I searched around on the internet and I see that many people took different approaches to this problem resulting in people either getting my answer or the attached answer.

Are they both technically right? It feels as though that a lot of these physics problems come down to a matter of perspective.
It depends on how you are relating ##\hat i## and ##\hat j## to compass directions.
The usual would be i for E and j for N.
On that basis, what do you think the i component of "24 m, 36 degrees north of east" is? There is only one correct answer.
It might help if you compare with zero degrees N of E. Does sin or cos give the right answer?
 
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haruspex said:
It depends on how you are relating ##\hat i## and ##\hat j## to compass directions.
The usual would be i for E and j for N.
On that basis, what do you think the i component of "24 m, 36 degrees north of east" is? There is only one correct answer.
It might help if you compare with zero degrees N of E. Does sin or cos give the right answer?
The i component should be the adjacent side of that angle which would come out to be 24*cos(36). Is that correct? I've attached my work as reference (my apologies for it being a bit messy).

So would that mean the original attached image is wrong?
 

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quittingthecult said:
24*cos(36)
Yes.
The working in the image in post #1 is wrong.
 
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haruspex said:
Yes.
The working in the image in post #1 is wrong.
Thank you!
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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