A VIRTUAL LAB ON MECHANICAL AND ELECTRICAL COMPOSITION OF HARMONIC OSCILLATIONS OF THE SAME FREQUENCY

Virtual laboratories are very effective tools in teaching Physics. Many basic topics in all general Physics courses for engineering degrees can be explained in a simple and intuitive way by means of these tools.

In this work, we present a user-friendly virtual laboratory (developed using the tool “Ease Java Simulations” for the study and understanding of the superposition of two harmonic oscillations of the same frequency and direction. This is a basic topic in Physics, since it is related to many phenomena in Mechanics, Electromagnetism, Optics, alternating current (AC) circuits, etc.

The user can select the parameters of two harmonic oscillations: amplitudes, initial phases, and the common period. The selections are made by means of sliders, enabling the laboratory to provide an interactive real time response showing how the changes affect the result. The user can see, both analytically and graphically, that the sum of the representative complex phasors of the harmonic oscillations provides the complex phasor of the superposition. Moreover, an animation shows that the phasors, when rotating in the complex plane, generate the sinusoidal time series of the corresponding oscillations.

In addition to this, the user can choose either a mechanical (springs) or electrical (AC current) animated graphic representation of the process. In this way, it can be seen that the amplitude of the superposition is not, in general, the sum of the composed harmonic oscillations amplitudes.
In order to increase the audience, the virtual laboratory offers the possibility of changing the interface language (Spanish, Valencian or English).

Note: The link to the virtual laboratory is http://personales.upv.es/mhgimene/FasoresML/FasoresML.xhtml