https://www.physlab-wiki.com/ 2026-04-17T22:03:23+00:00 https://www.physlab-wiki.com/ https://www.physlab-wiki.com/lib/tpl/UChicago/images/favicon.ico text/html 2025-01-10T13:26:55+00:00 Anonymous (anonymous@undisclosed.example.com) https://www.physlab-wiki.com/phylabs/lab_courses/phys-140-wiki-home/winter-experiments/coulombs-law-lab/coulomb_s_law_force_derivation?rev=1736533615&do=diff Introduction Consider two fixed point charges, $q_{1}$ and $q_{2}$, separated by a distance $r$. Coulomb discovered experimentally that the electrostatic force $F$ on charge $q_{2}$ due to its interaction with $q_{1}$ is given by the equation (1) $F = k \frac{q_{1} q_{2}}{r^{2}}$ Since $F$, $q$, and $r$ are all defined, $k$ becomes a constant of proportionality which must be determined experimentally. Equation (1) is now known as Coulomb's law.$q$$q = \int Idt$$I = \frac{dq}{dt}$$k = \frac{1}{… text/html 2024-07-23T12:15:54+00:00 Anonymous (anonymous@undisclosed.example.com) https://www.physlab-wiki.com/phylabs/lab_courses/phys-140-wiki-home/winter-experiments/coulombs-law-lab/marks-analysis?rev=1721751354&do=diff Setting The Gap Height gauge = 5.96mm +/- 0.02mm What limits precision? * Slight amount of play in measurement based on how tight you adjust the mic. Initial mic settings A = 8.18mm +/- 0.03mm B = 9.50mm +/- 0.03mm C = 9.37mm +/- 0.03mm What limits precision?$F=12.31 \pm 0.07 d - 0.15 \pm 0.10$$D = 0.0012mm \pm 0.0001 * F + 0.0003mm \pm 0.002$$d = D - (.0012 D - 0.0003)$$F = 12.06 \pm 0.06 D - 0.11 \pm 0.09$$F = 12.05 \pm 0.29 D + 0.003 \pm 0.37 $ text/html 2026-03-03T14:06:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://www.physlab-wiki.com/phylabs/lab_courses/phys-140-wiki-home/winter-experiments/coulombs-law-lab/marks-final-notes?rev=1772564778&do=diff Marks Final Notes - Coulombs Law General Notes * This lab really fits into the theme of making precision measurements, estimating uncertainties, deciding when your data is “good enough”, etc. from Autumn quarter. But here it is in Winter quarter. Not that there is anything wrong with that. text/html 2026-03-03T14:46:31+00:00 Anonymous (anonymous@undisclosed.example.com) https://www.physlab-wiki.com/phylabs/lab_courses/phys-140-wiki-home/winter-experiments/coulombs-law-lab/setup?rev=1772567191&do=diff Setup page for PHYS142 Coulomb's Law lab. Day One Apparatus The figure below shows all of the apparatus needed for a single station for both days of the lab. Not all apparatus should be set out at the student stations however. The masses for the whole room should be should be in the general apparatus area over on the bench by the blackboard. This mass collection should contain a variety of masses generally found in the lab including things like mass clips, air cart masses, etc. The idea i… text/html 2026-01-26T11:09:48+00:00 Anonymous (anonymous@undisclosed.example.com) https://www.physlab-wiki.com/phylabs/lab_courses/phys-140-wiki-home/winter-experiments/coulombs-law-lab/start?rev=1769443788&do=diff Experiment Setup Electrostatic Forces (PHYS142 - 2025) Introduction In this experiment you will measure the electrostatic force between plates of a parallel plate capacitor and compare your results with predictions derived from Coulomb's Law which can be written as,$$F = \frac{\epsilon_{\circ} A V^{2}}{2 d^{2}}.$$$\epsilon_{o}$