My Buddies 20% Time

A roller coaster works by getting pulled up a little hill in the beginning by a train. Then it goes down by pure momentum, without gravity, roller coasters would not work. It is all based on gravity, a lot of math is also used. In the past, they were made by wood and were not as strong and were not as safe. They would have to be repaired a lot.

Now, we have roller coasters that metal now. They are much better now.

A video on how roller coasters work: [youtube][/youtube]

My screenshots: