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*From*: "Albert J. Mallinckrodt" <ajm@cpp.edu>*Date*: Wed, 26 Aug 2020 18:04:24 +0000

From your description I imagined a graph that was picking out one or two specific, but otherwise arbitrary points to say something about, as in constructing a chord that will become a tangent line as t_1 and t_2 approach each other.

In the case of your figure I only wonder why you don’t label the distance of the release point below the x-axis as “Y” to complement your “X.”

John Mallinckrodt

Cal Poly Pomona

On Aug 26, 2020, at 9:45 AM, Carl Mungan via Phys-l <phys-l@mail.phys-l.org> wrote:

Maybe nothing wrong, but why “1”?

When discussing something like this in class, wouldn’t you say let’s pick an arbitrary point in the motion of the object and call it x(t)? I wouldn’t put a subscript 1 on it unless point 1 were some definite poinof interest (like a turning point, or when the object passes me, or whatever). But I want to point to some point on the graph.

Maybe I’m the only one who does this kind of thing.

Here’s an example - Fig. 1 in this paper of mine. Notice I did not label the axes in order to avoid this problem, but that’s kind of a cop-out:

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On Aug 26, 2020, at 11:31 AM, Albert J. Mallinckrodt <ajm@cpp.edu> wrote:Maybe I’m misunderstanding, but what’s wrong with say “x_1” and “t_1”?

_______________________________________________On Aug 26, 2020, at 7:46 AM, Joseph Bellina via Phys-l <phys-l@mail.phys-l.org> wrote:I think it is a bad idea to label a point in the curve with symbols since the point represents specific values. A good question to ask about the graph is what is the meaning of the points that make up the line to emphasize concretely that each point on the graph in your example represents The position of the object at some particular clock reading

You could label the spots x= the value and t= the value but not x and t

My thoughts. Stay well

Sent from my iPhone

On Aug 26, 2020, at 10:29 AM, Carl Mungan via Phys-l <phys-l@mail.phys-l.org> wrote:_______________________________________________

This is a minor matter, but it bothers me and I’m wondering if there’s an alternative?

Suppose we have a graph. Let’s say it’s position x in meters vs time t in seconds for definiteness. Draw the axes. Label with a symbol what is being plotted on each axis. Sketch in some arbitrary curve. Choose an arbitrary point on that curve. Draw dashed lines that run parallel to each axis and intercept the other axis. Label with a symbol each of these intersection points to indicate the coordinates of that arbitrary point.

Okay, what did you come up with for those two sets of labels (those labeling the axes and those labeling the coordinates of the point)?

I come up with the same labels in both cases, namely x on the vertical and t on the horizontal.

It bothers me to have the same labels in two different places on the axes like that (one at the ends of the axes perhaps, and one at some arbitrary “intermediate” point along them).

Comments?

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**Follow-Ups**:**Re: [Phys-L] Ex: Re: axes labels***From:*"Albert J. Mallinckrodt" <ajm@cpp.edu>

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