How Does the Height of a Person Affect a Bungee Jump?

Bungee jumping involves a simple conversion of energy. The jumper starts at the top of the jump with gravitational potential energy. This energy changes to elastic potential energy at the bottom of the fall. The jumper's height will have an impact on the amount of energy that gets converted. However, the impact will not be very significant unless it coincides with differences in height.

  1. Distance of Fall

    • Bungee cords are usually attached to jumpers by a harness at their waists. Taller jumpers will have slightly higher waists, so the distance from where the jumper starts to where she ends will be slightly longer even between jumpers of the same weight. The difference is small enough that it will not be noticeable to the jumper. It is negated if the bungee is attached instead to the jumper's ankle, although this method is not considered as safe.

    Total Energy

    • Taller jumpers with higher waists will also have a slightly longer distance from where the cord is attached to their waists to where this same end of the cord would fall naturally if dropped vertically and not tied to any weight. The particular distance (known as l) is relevant to calculating the amount of energy that will be converted with the jump. The amount of energy can be calculated by multiplying l with the jumper's weight and with the rate of acceleration due to gravity. The result will be slightly greater for taller jumpers, but the difference is nearly negligible since the few inches of difference between waist heights is very small in proportion to the total distance of l.

    Relationship of Height to Weight?

    • Taller people generally weigh more than shorter people, and the jumper's weight is also part of the calculation of the amount of energy to be converted. Differences in weight have a more direct and significant impact on the total amount of energy than can differences in height. A person who weighs twice as much will convert twice as much energy when jumping.

    Stretch Length of Cord

    • The jumper's weight will have a measurable impact on how far the cord stretches with the first jump. Heavier people will cause the cord to stretch more, which will mean that they will fall further and reach closer to the ground. It is important to customize the length of the rope to the weight of the jumper so heavy jumpers don't hit the ground in a setup that had been safe for a lightweight jumper. Differences in jump lengths can be mediated by using stiffer cords for heavier jumpers and softer cords for lighter ones. Consider also adding a static safety rope that is customized to the height of the individual.