Bungy Jumping

While studying abroad in Sydney, Australia, I had the opportunity to spend a week in Queenstown, New Zealand. Queenstown, known as the adventure capital of the world, is home to the Kawarau Bridge, the location of the world’s first commercial bungy jumping operation. I had never considered bungy jumping before my week in Queenstown, but once I got there, the locals convinced me I had to while in New Zealand. Exactly one year ago today, I jumped off of the Kawarau Bridge.

The Kawarau Bridge is 43 meters above the river below. It is an option for some to be dunked in the river at the bottom of the jump – full body, just your head, or even just your hair and fingertips. Given that I was very afraid of water as a kid, and to this day fairly apprehensive about swimming and being around water, I was absolutely not interested in hitting the water. Therefore, I stood on the edge of the bridge for a full two minutes unable to jump, having convinced myself I was going to be dunked in – even though I said I didn’t want to. The nice men working the bungy thought this was hilarious – I wasn’t scared to jump off a bridge, but I was scared of going head first into the river below. They convinced me that it wasn’t even an option for me if I wanted to, since I didn’t weigh enough to make it that far down.

At the time, I didn’t understand the physics behind bungee jumping and therefore was unsure about hitting the water. How that I understand the physics, I understand that given the spring constant of the bungy cord used (I tried to find this online and couldn’t) and given the potential energy I had on the bridge – mgh = 50kg*9.8m/s²*43m = 21070 J – I could not have reached the spring potential energy necessary for the change in length needed in order to reach the water, given the conservation of energy.

Therefore, I now understand why I had nothing to be worried about!