Vectors -- Adding velocity vectors to make a resultant

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Homework Help Overview

The discussion revolves around determining the resultant of two velocity vectors, A and C, given their magnitudes and directions. Vector A is specified as 44.0 at 28 degrees north of east, while vector C is given as 31.0 at 90 degrees south of east.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants discuss the initial attempt to subtract the magnitudes of the vectors directly, questioning the validity of this approach given the vectors' different orientations. Suggestions are made to express the vectors in different forms and to sketch them for better understanding. There is also a note on the unusual description of vector C's direction.

Discussion Status

The discussion is ongoing, with participants providing guidance on how to approach the problem, including sketching the vectors and considering vector addition rules. There is no explicit consensus on the correct method yet, as various interpretations of the problem are being explored.

Contextual Notes

Participants note the absence of the referenced figure (Fig. 3-32) and question the clarity of the directional specification for vector C. There is also mention of potential arithmetic errors in the original attempt.

APphysicsOR
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Homework Statement



Determine the vectors A-C, given the vectors A and C in Fig. 3-32. Vector A=44.0 at 28 degrees north of east and vector C=31.0 at 90 degrees south of east.

Homework Equations


I don't know any.


The Attempt at a Solution


44.0-31.0=11.0, 28.0-90= -62
The answers are 64.6 and 53.1 degrees.
 
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Hmmm... you took 2 vector lengths, and subtracted them. That works if they're parallel, but not at different angles.

Write your vectors in a couple different forms and post back. (I'm sure you've seen different ways to express the same vectors)
 
APphysicsOR said:

Homework Statement



Determine the vectors A-C, given the vectors A and C in Fig. 3-32. Vector A=44.0 at 28 degrees north of east and vector C=31.0 at 90 degrees south of east.

Homework Equations


I don't know any.

The Attempt at a Solution


44.0-31.0=11.0, 28.0-90= -62
The answers are 64.6 and 53.1 degrees.
We don't see Fig. 3-32, but I assume you do.

First step, sketch the vectors in their given orientation so you can see what you are dealing with.

Second step, remember the rule that says to subtract a vector you can reverse its direction and add it.

BTW, you might need to brush up on your arithmetic, too. :wink:
 
It's unusual and longwinded to describe a direction as 90 degrees South of East. Are you sure you have that specification correct?
 

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