English

Hourglass of constant weight as an illustrative example of a system with a variable mass

Physics Education 2023-02-16 v1 Classical Physics

Abstract

We provide an alternative approach to a problem posed in the article "Hourglass of Constant Weight" by Volker Becker and Thorsten P\"{o}schel, which appeared in Granular Matter 10 (2008), 231-232, i.e. 14 years ago. Our goal to return to this article after so much time is purely pedagogical. Although there is a slight and subtle inaccuracy in the derivation of equation (8) in the work of Becker and P\"{o}schel, which we correct, we use this circumstance only to give a detailed pedagogical exposition of an excellent physical problem and to show the pedagogical usefulness of the concept of momentum flux when considering the mechanics of systems with variable mass.

Keywords

Cite

@article{arxiv.2302.07830,
  title  = {Hourglass of constant weight as an illustrative example of a system with a variable mass},
  author = {Vladimir V. Kassandrov and Zurab K. Silagadze},
  journal= {arXiv preprint arXiv:2302.07830},
  year   = {2023}
}

Comments

14 pages, 3 figures, to be published in Granular Matter