It's been a race against time, building an early warning detection system for earthquakes before it's too late. It's not a question of if, it's a question of when the next big one is going to hit. Now all across Los Angeles, thousands of Angelenos downloading an app that a warned of a 5.0 earthquake or greater, relying on a network of sensors touted as the most advanced in the world.
This is really about precious seconds, you may have five seconds and this gets to you in two seconds and you have three seconds to get underneath a table. The warning could offer people anywhere from a few seconds to over a minute to prepare. That could give emergency rooms a chance to stop operating, trains to slow down, school kids to take cover, countries like Japan and Mexico have had similar systems for years with mixed success. This system, part of a pilot project that'll eventually cover the west coast including Alaska hit with a 7.0 quake in November, promising precious seconds of warning before the ground starts to shake.
They applied this principle all across the Roman Empire.
Slight difference because of air resistance, it will slow down a bit.