Space Needle

This past summer, I went to Seattle, WA and had the opportunity to stand on the observation deck of the Space Needle. This structure is very tall. I didn't know it back then but there is a lot of physics involved in this marvel.

The potential energy of me standing on that observation deck was very big. Using the potential energy formula, PE = mgh, where m = mass (kg), g = gravitational pull, and h = height (m), I could tell that the potential energy was going to be high since g = 9.8 and h = 160 m. If I knew my mass in kg I would tell you the exact amount of potential energy I had but I can't. Nevermind. I found out how to convert my weight into kg. Well, since I am 59 kg, my potential energy is 92,512 J (59 x 9.8 x 160).

Suppose I felt like falling off the Space Needle. My kinetic energy would be very big, too. In fact, at the moment I would hit the ground I would have the same amount of kinetic energy as I had potential energy at the top of the observation deck since energy cannot just disappear or suddenly be added. Instead it changes from potential to kinetic energy.

Since KE = 1/2 mv^2, and KE at the bottom = PE at the top, I was also able to find out that the speed at which I would hit the ground would be 56 m/s if there were no air resistance. Falling from this height would be very painful.