Huygens and Bernoulli's brachistochrone - Rijksuniversiteit Groningen

H&B – p.10/27Evolute and evolventSocietal problem in 17th century:determination of longitude at sealongitude ∼ time (360 = 15 × 24)pendulum clock: period increases with amplitudeTo find adapted, isochronous pendulumIdea: ‘cheeks’ shorten length l,hence shorten period, at larger amplitudeWhat is the shape of these ‘cheeks’?(musea Boerhaave, Hofwijck, Teylers)Related problems- Period as a function amplitude (elliptic integrals)- Geometrical properties of curves and their evolute