P1_8 Ballet Dancer

Abstract

In this paper, we investigated the effect of a female dancer’s arms on their rotational kinetic energy and therefore how fast they are turning during a pirouette. We did this by calculating the rotational kinetic energy change of a dancer when they have their arms fully outstretched and when they have their arms 50% closer to their rotation axis. In this case, the arm length of the dancer is the dancer’s radius when turning. Using the dancer’s moment of inertia in both scenarios, we found that the rotational kinetic energy change was a 320% (2 s.f) increase when the dancer’s radius was halved. This implies that the dancer’s angular velocity will also increase.