Vector Notation Inconsistencies

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LearninDaMath
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My teacher writes 3 dimensions like this:

Three-dimensional coordinate axes labeled z (vertical), y (horizontal to the right) and x (toward the viewer, lower left), with a point above the x-y plane shown by a green vertical line, blue and red dashed-style guide lines to the axes.



My textbook writes it like this:

3D coordinate axes with y pointing up, x pointing right and z pointing toward the lower left; a dot sits above the point where red and blue dashed-style lines meet a green vertical line.




If my online H/W is not directly written by my teacher and not directly written by my textbook (MasteringPhysics online HW), then when presented with a vector such as:

A = (2,1,-4)

Should I read it as:

A = (2x, 1y, -4z) or A = (2z, 1x, -4y)


I'm going to guess the H/W is more in line with the teacher's convention than my textbook's convention and that's how I'm going to proceed. However, if anyone has more insightful input as to how to read this vector, I'm all ears.
 
x= 2, y=1, z= -4

The coordinate system is a matter preference both is correct but a point is identified as (x,y,z)
 
RTW, I appreciate your response, thanks.

P.S.

"is" ..."are...it's all the same to me. ..Good thing this good place is not called "Grammerforums" :)
 
LearninDaMath said:
My teacher writes 3 dimensions like this:

Three-dimensional coordinate axes with z pointing up, y pointing right and x pointing toward the lower left, with a point above the x-y plane and dashed guide lines to its base.



My textbook writes it like this:

Three-dimensional coordinate axes with y pointing up, x pointing right and z pointing toward the lower left, with a dot above the x-z plane connected by a green line to the plane and red and blue lines outlining a rectangle.




If my online H/W is not directly written by my teacher and not directly written by my textbook (MasteringPhysics online HW), then when presented with a vector such as:

A = (2,1,-4)

Should I read it as:

A = (2x, 1y, -4z) or A = (2z, 1x, -4y)


I'm going to guess the H/W is more in line with the teacher's convention than my textbook's convention and that's how I'm going to proceed. However, if anyone has more insightful input as to how to read this vector, I'm all ears.

The two coordinate systems are the same. Both are "right-handed." They're just viewed from different orientations. Take the first one and rotate it 90 degrees counterclockwise around the x-axis. Then rotate it 90 degrees around the y-axis. The result is what is shown in the second diagram.

To actually *change* the coordinate system, (e.g. to make it "left-handed"), you'd have to change which direction is positive for one of the axes.

Now, to actually answer your question: when vectors are written down in terms of a comma-separated list of their Cartesian components in parentheses, the ordering is always (x,y,z). To do anything else would be very unusual and probably lead to confusion.
 
cepheid said:
The two coordinate systems are the same. Both are "right-handed." They're just viewed from different orientations. Take the first one and rotate it 90 degrees counterclockwise around the x-axis. Then rotate it 90 degrees around the y-axis. The result is what is shown in the second diagram.

To actually *change* the coordinate system, (e.g. to make it "left-handed"), you'd have to change which direction is positive for one of the axes.

Now, to actually answer your question: when vectors are written down in terms of a comma-separated list of their Cartesian components in parentheses, the ordering is always (x,y,z). To do anything else would be very unusual and probably lead to confusion.


I actually had to pick up the nearest box shaped item in my vicinity and rotate it to prove it to myself lol.

I appreciate your feedback, thanks.