Stuck on a few Vector homework problems

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The discussion revolves around difficulties with vector homework problems, specifically in calculating vector sums A+B and differences A-B for questions 1b and 2b. The user expresses confusion about using the Right-Hand Rule for determining vector directions in problem 4, particularly when vectors lack specific values. Additionally, there is uncertainty regarding question 5, especially the concept of calculating vectors "with respect to the Earth." The forum participants encourage the user to share their work for better assistance. Overall, the user seeks clarity on fundamental vector concepts in their Physics course.
PhantomDiclonius
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Homework Statement
Write out the vectors A+B and A-B in terms of the unit vectors i and j. Show them on your coordinate system.

Use the Right-Hand-Rule to determine the direction of the following:

Determine Speed and Direction with respect to the Earth.
Relevant Equations
[(A)^2 + (B)^2]

ArcTan = (Y/X)

ixj, ixk, jxk, ixi
I'm stuck on a few Vector homework problems. I don't quite understand how to write vectors A+B and A-B for questions 1b and 2b. I tried starting with calculating the magnitude for vector A+B on question 1b and then followed by finding theta, but I'm not sure if that's what I'm supposed to do.

I'm also completely flabbergasted by problem 4 where I'm supposed to use the Right-Hand-Rule to the direction of vectors such as i x i, how am I supposed to determine the direction if the vectors have no values?

Lastly, I'm pretty lost with question 5. I thought I did 5a correctly, but the part that asks "with respect to the Earth" makes me feel uneasy. I don't understand how to calculate something with respect to the Earth, I just tried calculating the barge in comparison to the river speed the best that I could.

Sorry, this is my first week in Physics and I'm feeling pretty lost, any help would be greatly appreciated, here's a pic of the worksheet and my work so far, thank you for your time:
 
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Welcome to the PF.
PhantomDiclonius said:
I'm stuck on a few Vector homework problems. I don't quite understand how to write vectors A+B and A-B for questions 1b and 2b. I tried starting with calculating the magnitude for vector A+B on question 1b and then followed by finding theta, but I'm not sure if that's what I'm supposed to do.
Let's take these questions one at a time. Please show us your work adding the components of the first vectors, then we can go on to your other questions. Thanks.
 
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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