I've always wondered how much energy a penny would have flying off the entire energy so I finally decided to actually figure it out. The Empire State building is about 381m but from the tip 443m. Lets say we want to go big time and drop it from the tip. A penny weighs about .0025kg. Before taking physics I had no clue how to find potential energy until my magnificent teacher Mr. Fullerton. He taught me that to find potential energy you need to use the equation PE=mgh. That would be (.0025kg)(9.81m/s)(443). That would be about 11 Joules. After finding this out I am pretty disappointed :/. I was hoping I could throw a penny off the tip and actually harm someone but oh well.