A mass hangs at the end of a length L of string making a pendulum.
The time it takes the pendulum to complete a swing (the period
T, our y variable, measured in seconds) is recorded for various
pendulum lengths (x, measured in m).
The accuracy of the period measurement is 0.04 s.
According to Newton's laws:
T = 2 π (L/g)1/2
where g = 9.8 m/s2 is the acceleration of gravity.
If we compare this expression to the generic power law relationship we find:
B = 1/2
A = 2 π/g1/2
or
g = (2 π/A)2
- Fit this data to a power law relationship.
- Consider Newton's scientific claim of a power law.
Does this evidence (data) confirm or contradict this claim? Support
your answer quantitatively.
- Properly report (sigfigs, error, units) the exponent for
the best-fit power law.
- Do an additional fit with the exponent held fixed at 0.5.
- Properly report (sigfigs, error, units) the A parameter for this second fit.
- Use a spreadsheet to calculate the acceleration of gravity from A, and properly report
(sigfigs, error, units) the value.
- Self-document the spreadsheet and turn in a hardcopy of the page.
- Make a hardcopy plot of the data with best-fit curve. Make an additional hardcopy plot
with scales chosen so as to linearize the curve.
- Turn in fit reports from both fits (i.e., steps 3 and 4).
X (m) | Y (s)
|
---|
0.20 | 0.85
|
0.23 | 0.95
|
0.28 | 1.12
|
0.38 | 1.20
|
0.40 | 1.22
|
0.44 | 1.34
|
0.60 | 1.59
|
0.89 | 1.86
|
1.71 | 2.57
|
2.00 | 2.82
|