Lab_Report_Notes

Notes for Momentum Lab 11/25
You should include your vf/vi vs mA and KEf/KEi vs mA plots. Likely no other plots will be necessary.
You can write this lab report however you want, but maybe the easiest thing would be to say something in your abstract like “We studied how the mass distribution of colliding objects affected the change in velocity and kinetic energy before and after an inelastic, stationary target collision. We found (or maybe didn’t find) that the ratio of final to initial velocities and ratio of final to initial kinetic energies was proportional to the mass of the incoming object with proportionality constant ____ which does (or maybe doesn’t) align with our prediction.” Then support this claim with the rest of the report.
PLEASE DO NOT REFERENCE INDIVIDUAL DATAPOINTS. Typically, any data you present should be in the form of a plot.
Please don’t forget units and uncertainty on every measured value.
Rules for Uncertainty
EVERY measured value has uncertainty
Percent error from expected is NOT uncertainty. Technically, percent error from expected should have its own uncertainty
Uncertainty/error bars are due to random error, discrepancy from expected value is due to systematic error
It should be explained what errors contribute to an error bar/uncertainty, and these errors should probably be random
A discrepancy in measured vs expected should be blamed on a systematic error, not a random error, and DEFINITELY should not be blamed on a random error accounted for in the uncertainty of your measured value or else that uncertainty would encompass the measured value
Don't use the word "actual" because it's unclear whether this means measured or expected
Uncertainty is not mismeasurement. You should not attribute uncertainty to rounding error, miscalculation, mismeasurement, or "human error".
You should almost never mention a best-fit line, and if you do, do not say it has uncertainty because it doesn't.
More Rules
Your physics should be correct, and you should do a reasonable job of deriving the formulas relevant to your prediction. Don't just recite them.
EDIT: You need to make a reasonable effort to derive the equations in your prediction. For example, If you’re expecting a sin(angle) dependence, that’s an important part of the lab and you need to describe where the sin comes from.

Do not dump data. If you report a number, the number should be meaningful to your conclusion and not part of a larger dataset. If you have multiple numbers you want to report, it should be in the form of a plot that is meaningful to your conclusion. There are few scenarios where you should recite measured values in a sentence or list measurements in a table. You also don't need to report everything you measured in the lab.
Do not just recite a few data points and make a conclusion. You should, in general, never recite data. Instead, reference a plot and make conclusions from that. Similarly, don’t mention what your prediction predicts each datapoint to be. You only need to talk about characteristics of your plots (slope, shape, etc) and then you compare what your prediction says about those characteristics. For example, “We found this plot to have a slope of 8m/s^2 +/- 1, however, we predicted it to have a slope of 9.8m/s^2.” You don’t need to say, “at an angle of ____ we found an acceleration of ____, however, our prediction implies it should have had an acceleration of ____, etc.”
EVERYTHING needs proper units.
"correlation", "linear", "proportional", "expectation value", "confidence interval", and "statistically significant", among others, are loaded terms, and you should only use them if you know what you're talking about. Note that if f(x) = m*x + b, f(x) is not linear with x or proportional to x unless b=0.
Don't seem like you're making up error to get your result to match the expectation even if you did.
Don't just say you're showing that all your quantities of interest are related. Pick a specific relation and justify it. For example, don't say "we showed velocity, acceleration, displacement, and angle are related". Say "we showed that acceleration is proportional to the sin of the angle".
You can disregard what the guide says about a "hypothetical scenario"
Use the words "confirms", "proves", "verifies", "implies", etc. sparingly, if at all, in favor of words like "supports", "demonstrates", "indicates", "suggests", etc.
Plots need titles, descriptions, legends, and axis labels with units.
Present your report as if you are testing a theoretical prediction with an experiment. Don't present your report as you are using a theoretical prediction to test the legitimacy of your experimental methods. In the end, you shouldn't claim more than whether your experiment aligns or doesn't align with theory.

Please let me know if you have any questions. Good luck on the lab report!