TY - JOUR
AU1 - Inman, Fred
AB - The measurement of fundamental constants is common practice in instructional laboratories. A number of the equipment manufacturers have developed apparatus for such applications, e.g., the determination of e by the Millikan oil drop method or the determination of the speed of light with fiber optics. Other experiments determine not a single constant, but a combination of constants, e.g., e/m; by electron beam deflection in a magnetic field or h/e; by the photoelectric effect. About 30 years ago Carl E. Miller and I 1 proposed a method of measuring e/k; , the ratio of the electron charge to Boltzmann's constant, that was reasonably simple but not necessarily inexpensive because it involved the use of a sensitive electrometer. In recent years, however, inexpensive digital multimeters (DMM), many costing less than $30, have found their way into the physics laboratory. The purpose of this paper is to suggest the use of two DMMs, one operating as a voltmeter and the other as an ammeter, in a simple circuit involving a junction transistor and a variable potential source. Even the potential source can be quite simple, a 1.5-V battery and a 1-kΩ potentiometer, as shown in Fig. 1. If available, a variable dc power supply replacing the battery and potentiometer would be more convenient.;
TI - A Simple Laboratory Experiment to Measure e/k;
JF - The Physics Teacher
DO - 10.1119/1.1845986
DA - 2005-01-01
UR - https://www.deepdyve.com/lp/american-association-of-physics-teachers/a-simple-laboratory-experiment-to-measure-e-k-Pp2s1Kj93G
SP - 27
EP - 28
VL - 43
IS - 1
DP - DeepDyve
ER -