Improvements to the Millikan oil drop experiment as it is performed in teaching laboratories are described. Enhancement of the optics in the oil‐drop apparatus greatly improves the visibility of the drops. Accurate timing of their motion becomes possible since they are now bright and sharply focused. With improved timing, the parameters such as microscope calibration and plate separation can become the principal sources of experimental error. Methods are described to accurately determine these experimental parameters. The workload for the experimenter is greatly reduced by using a computer to: act as a smart stopwatch, calculate the drop charge in real time, perform the statistics, and make records of the experiment. The convenience and speed offered by the computer, coupled with improved optics, relieves the eyestrain, fatigue, and frustration usually associated with this experiment. Nye’s watch oil was used in this study. A return to Millikan’s original iteration method for the correction to Stokes’ law lowers the calculated charge for small drops by about 2%. With these improvements the calculated charges are sufficiently accurate that guesswork as to the multiplicity of their charge is essentially eliminated. A student typically obtains the value of the electronic charge accurate to about 1% with 1 h of experimentation. Student and instructor satisfaction are much improved.
Skip Nav Destination
Article navigation
November 1995
Papers|
November 01 1995
The Millikan oil‐drop experiment: Making it worthwhile
Ray C. Jones
Ray C. Jones
Department of Physics, Southwestern Oklahoma State University, Weatherford, Oklahoma 73096
Search for other works by this author on:
Ray C. Jones
Department of Physics, Southwestern Oklahoma State University, Weatherford, Oklahoma 73096
Am. J. Phys. 63, 970–977 (1995)
Article history
Received:
May 05 1995
Accepted:
May 19 1995
Citation
Ray C. Jones; The Millikan oil‐drop experiment: Making it worthwhile. Am. J. Phys. 1 November 1995; 63 (11): 970–977. https://doi.org/10.1119/1.18001
Download citation file:
Pay-Per-View Access
$40.00
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Citing articles via
All objects and some questions
Charles H. Lineweaver, Vihan M. Patel
Ergodic Lagrangian dynamics in a superhero universe
I. L. Tregillis, George R. R. Martin
Interplay between Airy and Coriolis precessions in a real Foucault pendulum
N. N. Salva, H. R. Salva
It is time to honor Emmy Noether with a momentum unit
Geoff Nunes, Jr.
Solving introductory physics problems recursively using iterated maps
L. Q. English, D. P. Jackson, et al.
Related Content
Dual‐purpose Millikan experiment with polystyrene spheres
Am. J. Phys. (May 1975)
Millikan's Oil-Drop Experiment: A Centennial Setup Revisited in Virtual World
Phys. Teach. (February 2012)
The ‘Nut-Drop‘ Experiment—Bringing Millikan's Challenge to Introductory Students
Phys. Teach. (September 2009)
Millikan Movies
Phys. Teach. (September 2008)
Digital video microscopy in the Millikan oil-drop experiment
Am. J. Phys. (August 2005)