Inflatable Bungee Jumping
BUNGEE jumping was introduced to the British public 15 years ago by a group calling themselves “The Dangerous Sports Club “. In 1979 four members of this club attached themselves to the Clifton suspension bridge in Bristol, using elastic ropes, and jumped off. This action attracted the attention of both the media and the police.1 In these early days the term bungee jumping was not used; a subsequent leap from the Clifton suspension bridge was reported by The Times as a ~~ yo-yo leap”,’ The jumper in this case was fined a token sum.:’ Although relatively new in Britain, bungee jumping is an ancient activity. It has its roots on the South Pacific island of Pentecost where men jump from a high wooden tower in April and May attached by a vine. This ritual is performed to encourage the yam harvest. Following the initial headlines in Britain bungee jumping has steadily grown in popularity. It has been estimated that in 1993over 70000 jumps were made throughout Britain, many for charity. The respectability of the pursuit has also improved, although it is not always appreciated. In New Zealand bungee jumping has won awards for tourism but in Australia a government minister called it “glue sniffing for yuppies?” and the Zimbabwean government protested to Zambia over plans to allow bungee jumping from the Victoria Falls bridge, claiming this was not a fitting activity for a world heritage site.” As the motion involved in bungee jumping is essentially one-dimensional it makes an interesting case study for A-level or first-year undergraduate mechanics. Some basic integration and knowledge of simple harmonic motion is all that is needed to analyse a simple model of bungee jumping. There are clearly potential dangers involved in throwing yourself off a high platform. A variety of” injuries ranging from minor cuts and bruises to fatalities have been reported.” In France bungee jumping was briefly banned in 1989following three deaths. Eye injuries caused by bungee jumping featured recently in the medical literature.” Any sensible practitioner of the sport will want to know the answer to the question” Will I hit the ground?”. Some simple modelling can supply the answer.