Research Article

String Shooter’s overall shape in ambient air

¹ Observatoire de Paris, PSL Research University, 5 place Jules Janssen, 92190 Meudon, France
² Univ. Paris-Diderot, Université de Paris, Bâtiment Condorcet, 4 rue Elsa Morante, 75013 Paris, France
³ Univ. Paris-Sud, Université Paris-Saclay, Bâtiment 301, 91405 Orsay, France
⁴ École Normale Supérieure, PSL Research University, 45 rue d’Ulm, 75005 Paris, France

^* e-mail: margaux.abello@obspm.fr

Received: 1 June 2019
Accepted: 2 December 2019

Abstract

In this article, we study the behaviour of a looped string launched in ambient air using motorised wheels. We show that the loop, once it reaches its stationary state, is either in the pulley or the air-lifted state. The transition between these two distinct states occurs at the so-called takeoff speed. We prove that this speed differs from one string to another based on its characteristics. However, it is independent from the loop’s length and its initial launch angle. This speed indeed corresponds to the threshold where air drag starts compensating for the weight of the string.