Why is it important to check the magnitude of vectors when adding them?

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Checking the magnitude of vectors when adding them is crucial to ensure accuracy in results. In this discussion, a user initially miscalculated a resultant vector's magnitude due to a typographical error in their calculations. They mistakenly multiplied instead of dividing by their scale factor, leading to an incorrect speed of 23.6 m/s instead of the correct 5.9 m/s. The conversation highlighted the importance of verifying calculations and understanding vector relationships, particularly when angles are involved. Ultimately, confirming the magnitude helps prevent errors in vector addition.
ryanking93
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Homework Statement
Add the following vectors and determine the resultants (length, angle from O)
Relevant Equations
3 m/s. 45° + 5 m/s. 135°
So I've charted the equation above, and received the correct resultant 104.0° I used a scale of 1m/s = 2cm and I get 11.8cm which gives me 23.6m/s but when I look at the answer it is 104.0° / 5.83N

I have no idea why its in Newtons.
 
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Welcome! :smile:
Could you post the original text of the problem?
The value you found is not correct.
 
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Lnewqban said:
Welcome! :smile:
Could you post the original text of the problem?

Thank you. I have attached both the questions and answers I am referencing. The specific question is "C"

And my answer to the question.
 

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Typographical error.
 
OmCheeto said:
Typographical error.

Okay, Thank you. I thought I might be losing it for a minute.
 
ryanking93 said:
Thank you. I have attached both the questions and answers I am referencing. The specific question is "C"

And my answer to the question.
It is an error of the booklet, the resultant vector should be in m/s.
Note that the angle between your vectors is 90°, therefore, you could apply the Pythagorean equation and see that the result can't be 23.6 m/s.
 
Lnewqban said:
It is an error of the booklet, the resultant vector should be in m/s.
Note that the angle between your vectors is 90°, therefore, you could apply the Pythagorean equation and see that the result can't be 23.6 m/s.

Ahhhh I see now! My issue was when I ended up with 11.8cm instead of dividing by 2 I multiplied by 2. As my scale was 1m/s = 2cm. I end up with 5.9m/s.

Thanks a million for the help!
 
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ryanking93 said:
Ahhhh I see now! My issue was when I ended up with 11.8cm instead of dividing by 2 I multiplied by 2. As my scale was 1m/s = 2cm. I end up with 5.9m/s.

Thanks a million for the help!
When adding vectors, it is good to check that the result is not greater than the addition of the magnitude of each independent vector.
You are welcome. :smile:
 
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