A pair of perpendicular vectors

AI Thread Summary
The discussion revolves around calculating the resultant of two pairs of perpendicular vectors. For the first pair of 482.5 N vectors, the resultant is calculated using the Pythagorean theorem, yielding approximately 682.36 N. The second pair, consisting of 24 N and 31.1 N vectors, also uses the same theorem, resulting in approximately 39.28 N. Participants clarify that "acting at right angles" and "perpendicular" are synonymous, emphasizing that only the magnitude is needed, without concern for direction. The importance of including units in the final answers is also highlighted.
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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