What is the |vector A-vector B|

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The discussion revolves around determining the correct expression for the magnitude of the difference between two vectors, A and B. Participants suggest that option D (B - A) is a valid answer, while also considering other possibilities. It is clarified that option B (A - B) is incorrect because it results in a negative value, whereas the magnitude must be positive. The key takeaway is that the correct expression for the magnitude of the difference between the vectors is essential, emphasizing that the result should be a positive number. Understanding vector subtraction and its implications on magnitude is crucial for solving the problem accurately.
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Homework Statement



vector A: ------>
vector B; <----------

choices are:

A) Vector A-vector B
B) A-B
C) Vector B-vector A
D) B-A
E) Vector A + vector B
F) A+B
G) |vector B- Vector A|

I think the answer is D, but I am not sure. Also I think there is more than one answer. Can you guys please help me out. Thanks.
 
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s31t8n8 said:

Homework Statement



vector A: ------>
vector B; <----------

choices are:

A) Vector A-vector B
B) A-B
C) Vector B-vector A
D) B-A
E) Vector A + vector B
F) A+B
G) |vector B- Vector A|

I think the answer is D, but I am not sure. Also I think there is more than one answer. Can you guys please help me out. Thanks.

If I'm interpreting everything correctly, then D would be an answer. I do believe there is another true answer; what do you think it is, and why?
 
well, you have to line vector A on top of vector B and then perform the subtraction and you'll see that the resulting vector would look like :
vector A: ----->
vector B: <----------
answer :
<-----
 
louie3006 said:
well, you have to line vector A on top of vector B and then perform the subtraction and you'll see that the resulting vector would look like :
vector A: ----->
vector B: <----------
answer :
<-----

Right; and how is that resulting vector that you found related to what they are asking for in the problem?
 
alphysicist said:
If I'm interpreting everything correctly, then D would be an answer. I do believe there is another true answer; what do you think it is, and why?

im going to take a guess and say its B. if not could you please explain what the answer is? Thanks
 
s31t8n8 said:
im going to take a guess and say its B. if not could you please explain what the answer is? Thanks

The answer B is not correct because it would be a negative number; choice B says to subtract the length of \vec B from the length of \vec A. Since \vec A is shorter \vec B, then choice B is a negative number.

But |\vec A-\vec B| is a magnitude and therefore positive.

For the remember that the quantity you are looking for is a positive number, not a vector, and is the magnitude of the difference of the vectors. (I cannot give out answers here as that would violate forum rules.)
 
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