Publication details
Damping forces - a friend or a foe in explaining mechanical motion?
| Authors | |
|---|---|
| Year of publication | 2006 |
| Type | Article in Periodical |
| Magazine / Source | European Journal of Physics |
| MU Faculty or unit | |
| Citation | |
| Web | http://physics.muni.cz/~bartos/resdemexp.html |
| Field | Theoretical physics |
| Keywords | damping; force; oscillator; drag; Newton; Stokes; experiment |
| Description | The paper presents simle, cheap, easily accessible and for students impressive demonstration experiments for three typical examples of physical systems for which damping forces ought to be involved in the equations of motion: a body falling in air, a damped mechanical oscillator, and Foucault currents. Various models of such forces are studied within an elementary physical and mathematical approach. It appears, maybe as a slightly suprising result that a commonly used model of damping forces in mechanics - the air drag force linearly depending on velocity - is not realistic in many typical situations. Equations of motion are solved numerically with standard software packages even in cases where an analytical solution exists. Thus, the explanation of solved problems is on a level corresponding to an undergraduate university course of general physics. The results of these demonstration experiments are compared with graphical outputs of numerical solutions. |