A pair of perpendicular vectors

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Homework Help Overview

This thread discusses two questions involving the calculation of the resultant magnitudes of pairs of perpendicular vectors, specifically in the context of physics problems related to vector addition.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants explore the application of the Pythagorean theorem for calculating the resultant of perpendicular vectors. Questions arise regarding the necessity of directional components and the interpretation of the term "acting at right angles." There is also uncertainty about the correctness of calculations and the significance of signs in the context of magnitude.

Discussion Status

Some participants have provided clarifications regarding the use of the Pythagorean theorem and the concept of magnitude, indicating a productive exchange of ideas. There is acknowledgment of calculation errors and a general sense of increased understanding among participants.

Contextual Notes

Participants express concern over the wording of the problems and its impact on their understanding, highlighting the pressure that can accompany homework assignments.

ArcherofScience
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A pair of perpendicular vectors...

Homework Statement


This thread contains 2 questions that are similar.

A pair of 482.5 N vectors are perpendicular.
What is the magnitude of their resultant?
Answer in units of N

Two vectors of magnitudes 24 N and 31.1 N
act at right angles to each other.
What is the magnitude of their resultant?
Answer in units of N

Homework Equations



for the first one, what do u exactly do? just find the resultant and that's it? is their a magnitude sign such as north of east or something? do i have to find theta?

for the second one, what does it mean it acts of right angles ot each other? is it just the resultant or what?

The Attempt at a Solution



1st: 482.5 ^2 + 48.5^2= r^2
232806.25 + 232806.25 = r^2
√465612.50=r^2
r= 682.358 <----does it need a positive or negative sign?2nd: 24^2 + 31.1^2 = r^2
576 + 967.21 = r^2
√1543.21= r^2
r= 39.3219 <--- did I even solve this right? :confused::cry:
 
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ArcherofScience said:

Homework Statement


This thread contains 2 questions that are similar.

A pair of 482.5 N vectors are perpendicular.
What is the magnitude of their resultant?
Answer in units of N

Two vectors of magnitudes 24 N and 31.1 N
act at right angles to each other.
What is the magnitude of their resultant?
Answer in units of N

Homework Equations



for the first one, what do u exactly do? just find the resultant and that's it? is their a magnitude sign such as north of east or something? do i have to find theta?

for the second one, what does it mean it acts of right angles ot each other? is it just the resultant or what?


The Attempt at a Solution



1st: 482.5 ^2 + 48.5^2= r^2
232806.25 + 232806.25 = r^2
√465612.50=r^2
r= 682.358 <----does it need a positive or negative sign?


2nd: 24^2 + 31.1^2 = r^2
576 + 967.21 = r^2
√1543.21= r^2
r= 39.3219 <--- did I even solve this right? :confused::cry:

"acting at right angles" or "perpendicular" mean the same thing. And it means you can apply the pythagorean theorem, just like you did. And again, the word "magnitude" means you don't have to worry about signs. I get a slightly different number from you on the second one. Did you punch a calculator key wrong? And don't forget to specify units in your answer.
 


oh yeah i just realized my mistake, its 39.2837 i believe. but thanks for your help :redface:! i understand it i believe a bit more, just the way it was worded had me a bit pressured.
 


ArcherofScience said:
oh yeah i just realized my mistake, its 39.2837 i believe. but thanks for your help! i understand it i believe a bit more, just the way it was worded had me a bit pressured.

You are maybe worrying a bit more than you need to. And yes, I get 39.2837N. Don't forget the units!
 

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