Re: Linearizing Graphs

[THOMAS SANDIN <sandint@NCAT.EDU>]

        We often like to extract as much information as possible from our
straight-line graphs using their slopes and intercepts. In the simple
pendulum (small angle) case, we'd tell them the graph must go through
(0,0) and to eye-ball a best-fit straight line to the data.
        Graphing T^2 vs. L gives a slope of 4(pi)^2/g, so that the
students can solve for g from the slope.
        Possibly offending some purists, we have had them graph L vs.
(T/2pi)^2, giving g "magically" as the slope. (Find the slope. Is its
value equal--within experimental error--to a constant you recognize? ...)
                                                Tom Sandin

 On Tue, 19 Oct 1999, Ed Schweber wrote:
>    If we want to force a graph experimental data for period, T, of a
> pendulum vs its length, L, into being a straight line we usually plot T^2
> vs. L. But a graph of T vs sqrt(L) would also be linear and seems to be
> easier for students to understand. Is there any reason besides convention
> for doing it one way as opposed to the other?