Vector Solutions to Math Problem: 27V + 8<b>i</b> + 5<b>j</b>

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Homework Help Overview

The discussion revolves around a problem involving vector addition and magnitudes, specifically focusing on the expression 27V + 8i + 5j. Participants are examining the interpretation of vector magnitudes and their sums as defined in a particular textbook.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants are questioning the interpretation of the problem, particularly whether the value 27 represents the magnitude of the combined vectors or the sum of their individual magnitudes. There is a distinction being made between the sum of magnitudes and the magnitude of the sum of vectors.

Discussion Status

Some participants have provided clarifications regarding the definitions used in the problem, noting the difference between the sum of magnitudes and the magnitude of the sum of vectors. The conversation is exploring these interpretations without reaching a definitive consensus.

Contextual Notes

There is mention of specific definitions from the textbook regarding vectors and scalars, which may influence the understanding of the problem. Participants are also reflecting on their prior experiences with vector notation and operations.

pyroknife
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I attached the problem along with its answers. The letters in bold indicate a vector, the unbolded Vs are scalars (that's how they defined it in this book.) For the first unbolded one how did they get 27? shouldn't it be the magnitude of the combination of the 2 vectors?
 

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from your picture the magnitudes of the two vectors are 12 and 15, 12+15=27
the question is asking for [itex]|V_1| + |V_2|[/itex], the sum of magnitudes, rather than what I think you mean [itex]|V_1 + V_2|[/itex] which is the magnitude of a sum.

in general [itex]|V_1 + V_2| \leq |V_1| + |V_2|[/itex]

where [itex]|V|[/itex] is the magnitude of V
 
pyroknife said:
I attached the problem along with its answers. The letters in bold indicate a vector, the unbolded Vs are scalars (that's how they defined it in this book.) For the first unbolded one how did they get 27? shouldn't it be the magnitude of the combination of the 2 vectors?

No, they asked for [itex]V_1 + V_2[/itex], the sum of the magnitudes of the vectors. What you're suggesting is [itex]|\vec{V_1} + \vec{V_2}|[/itex], the magnitude of the sum of the vectors.
 
Oh thanks guys. That's what I thought it meant from the answer, but I've never seen anything like that before, it's always |V1⃗ +V2⃗
 

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