Imagine drilling a hole through Earth, hopping on a train powered by gravity alone and traveling through from one end to the other. How long would you spend on that “gravity train” before popping out on the other side?
Journey Through the Center of the Earth
A student calculates a more realistic answer to a classic physics homework problem.
By Sarah Scoles
Oct 6, 2016 5:00 AMNov 19, 2019 8:41 PM
If Mexico’s Cave of the Swallows cut through Earth, classic physics says that if you dove in, it would take about 42 minutes to pop out the other end. A new approach shortens that trip. (Credit: Omer Mei-Dan)
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