The physics of oscillatory motion: an experiment about pendulums

International Journal of Interactive Mobile Technologies (iJIM)

During pendulum analysis, the approximation for small angles is usually performed as a simple harmonic motion. However, for large angles, this approximation is not convenient so exact solutions are proposed by differ-ent methods. This paper presents the comparison of two solutions for the displacement of the pendulum in the domain of time and frequency, the solution by Jacobi elliptic function and the solution by the numerical method Dormand-Prince with the results of measurements obtained by means of a physical prototype designed for the teaching of physics. We consider that this comparative study allows a better understanding of the phenomenon of the non-linear pendulum in the students of undergraduate careers in the physics of waves as well as a previous training for the course of analysis of signals being in good exercise of teaching

Physics Education, 2010

The topic of coupled oscillations is rich in physical content which is both interesting and complex. The study of the time evolution of coupled oscillator systems involves a mathematical formalization beyond the level of the upper secondary school student's competence. Here, we present an original approach, suitable even for secondary students, to investigate a coupled pendulum system through a series of carefully designed hands-on and minds-on modelling activities. We give a detailed description of these activities and of the strategy developed to promote both the understanding of this complex system and a sound epistemological framework. Students are actively engaged (1) in system exploration; (2) in simple model building and its implementation with an Excel spreadsheet; and (3) in comparing the measurements of the system behaviour with predictions from the model.

In our discussion of the damped pendulum case we have dealt with two different types of damping,

Physics Letters A, 1994

A phenomenological equation of motion is proposed to account for two distinctive features of low-frequency inverted pendulums: frequency independent internal losses and instability at resonance frequencies below a critical threshold. The comparison with recent experimental data is discussed in detail. A new characterization of the background loss for a mass suspended as a pendulum by wires is also derived.

European Journal of Physics, 2005

We describe a 8085 microprocessor interface developed to make reliable time period measurements. The time period of each oscillation of a simple pendulum was measured using this interface. The variation of the time period with increasing oscillation was studied for the simple harmonic motion (SHM) and for large angle initial displacements (non-SHM). The results underlines the importance of the precautions which the students are asked to take while performing the pendulum experiment.

Physics Education, 2018

In the field of physics teaching, the simple pendulum provides a very simple way to study the harmonic oscillator, source of some fundamental concepts like periodicity, relaxation time and anharmonicity. As such, its experimental study is frequently integrated in the high school or first years university programs. With this in mind, in this article we propose a simple setup allowing to study some of its properties. By coupling a small wireless acquisition board to an oscillating mass, the centripetal acceleration is recorded and analyzed. We show using basic calculations how this acceleration allow to extract the variation with time of its period and of the amplitude. The experimental results show that the damping of the amplitude is very well described by an exponential law. The accuracy we obtain on the period allows to show that, not only it decreases with amplitude, but that this decrease is relatively well described by standard calculation. Using wireless multipurpose acquisition board and usual spreadsheet for experimental modelling, the completion of this work, about 4 hours, offers to the student an original way to go a little beyond the classical study of the spectacular object that is the pendulum.

arXiv: Classical Physics, 2019

The characteristics of drive-free oscillations of a damped simple pendulum under sinusoidal potential force field differ from those of the damped harmonic oscillations. The frequency of oscillation of a large amplitude simple pendulum decreases with increasing amplitude. Many prototype mechanical simple pendulum have been fabricated with precision and studied earlier in view of introducing them in undergraduate physics laboratories. However, fabrication and maintenance of such mechanical pendulum require special skill. In this work, we set up an analog electronic simulation experiment to serve the purpose of studying the force-free oscillations of a damped simple pendulum. We present the details of the setup and some typical results of our experiment. The experiment is simple enough to implement in undergraduate physics laboratories.