Mark Strehl Blog: How long would it take to fall through Earth?

Suppose that you could cut a hole in the Earth all the way to the other side. How long would it take you to "fall through?"

Either I was asleep, or my science teacher never mentioned it - apparently this has been a question asked in physics classrooms since 1966.

And the answer has been 42 minutes and 12 seconds.

I say "has," because some scientific genius actually looked into this and found the "actual" time (disregarding for a moment the fact that you can't actually dig to China from here!) was four minutes shorter than previously thought!

And the reason for that - I knew you would ask - is mass times gravity equals acceleration. This, Einstein figured out that the center of the earth is a lot heavier than thought 50 years ago.

It was thought that the center of the planet weighed 187 pounds per sq/ft. When in reality it weighs a whopping 811 pounds per sq/ft. Which would make you "faster."

Picture this: If you jumped in feet first, you would actually come out on the other side "upside down!"

And when you got to the other side...hang on. Otherwise you will be pulled back down the hole just like a ball on the end of a pendulum, ready to swing back to the other side!

Lay that one on your coworkers today around the water cooler.