Finding the position vector for translated frame of reference

AI Thread Summary
The discussion centers on finding the position vector in a translated frame of reference, specifically the y'-x' vector. A proposed vector is given as r = (8t - 1) i + (6t - 2) j, with reasoning based on the need for the position to be -1i -2j at t = 0. Questions arise about the validity of this reasoning and the relationship between the x'-y' and x-y systems. The conversation touches on the concept of relative frames of reference and the conditions for using inertial frames. Overall, participants seek clarity on the derivation and relationships of the vectors involved.
simphys
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Homework Statement
Please refer to the picture, I don't really have a question problem.
I was posed the question on how I would model what the position would be when the frame of reference is translated as shown on the picture.
Relevant Equations
##\vec r = 8t \hat i + 6t \hat j## for the y-x reference framse.
what would be the y'-x' ##\vec r## vector be?

I think it is
##\vec r = (8t - 1) \hat i + (6t - 2) \hat j## (not sure whether it is correct or not.)
I thought about it as at t = 0 the position needs to be -1i -2j so that is why I took the signs in the y'-x' frame position vector as a - instead of + signs for 1 and 2.

Is it ok to reason like this or do I need to derive it from somewhere else? I am not very acquianted with translation of the axes that's why I am asking.
Thanks in advance.

1658132327542.png
 
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What is the origin of x' y' system as measured in the x y system?
 
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drmalawi said:
What is the origin of x' y' system as measured in the x y system?
in points (1,2) = (x,y)
 
1658133200085.png

can you find a relation for the vectors ## \vec R##, ##\vec r## and ##\vec r\:'##?
 
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drmalawi said:
What is the origin of x' y' system as measured in the x y system?
oh wait, isn't this actually the 'relative frames of references' that are used to describe relative motion?
than it becomes r_x/p = r_x'/x + r_p/x' (where the condition was that it should be an inertial frame aka cst velocity or at rest for it to be valid)
 
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drmalawi said:
View attachment 304325
can you find a relation for the vectors ## \vec R##, ##\vec r## and ##\vec r\:'##?
yep exactly my post #5 no?
 
simphys said:
aka cst
?
 
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drmalawi said:
?
constant, apologies.
 
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simphys said:
constant, apologies.
np glhf
 
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