What is the |vector A-vector B|

[s31t8n8]

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.

 

[alphysicist]

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?

 

[louie3006]

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 :
<-----

 

[alphysicist]

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?

 

[s31t8n8]

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

 

[alphysicist]

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.)