A Short Story on... Mechanical Energy

Emma loved science. Ever since she was a litte kid, she loved to invent new trinkets, or try out an imaginative experiment. One day, when she was five, she tied a string attached to a bowling ball (don't fret! The string was a super strong material she created just a year earlier) to an iron bar on her ceiling. Being the cute mischievous five-year-old she was, she had people come up to the bowling ball and she would pull it back towards their noses, telling them not to move. After letting it go, it would swing forward, then back, approaching the person again. She maniacally laughed each time the person flinched or moved, for she knew the bowling ball would not hit them.  As she grew older, she also grew more intelligent, until she became a roller coaster engineer. Emma wanted to create Earth's wildest coaster, without any chains. So, she started a contest in which anyone could submit a design of their dream roller coaster. However, no design would be doable, for people made ignorant mistakes, like having the tallest hill at the end of the ride, or three loops in a row, none having a clothoid shape. Sitting, there, she played with her Newton's Cradle, watching the first ball hit the second and the fifth swinging up. She wondered, How can people be so dull-witted? I might just have to enter my own contest..., which is exactly what Emma ended up doing. Her design was zany, adrenaline rushing, and utterly nerve-racking, but most definitely doable. She would call it, the Deathinator. All was going well on the project, and it was soon opening day. Excitedly, Emma was about to cut the ribbon, when all the sudden, the Earth collapsed in on its self! But of course, as Emma knew, energy can only be converted from one form to another, so her last thought was proudly, Maybe our planet will burst into a million asteroids and ---, but the rest, the universe may never know.