How fast does things fall from the sky?
A: How fast something falls due to gravity is determined by a number known as the "acceleration of gravity", which is 9.81 m/s^2 at the surface of our Earth. Basically this means that in one second, any object's downward velocity will increase by 9.81 m/s because of gravity.
The first equation shows that, after one second, an object will have fallen a distance of 1/2 × 9.8 × 12 = 4.9 meters. After two seconds it will have fallen 1/2 × 9.8 × 22 = 19.6 meters; and so on.
- On the basis of the law of parabolic fall, Galileo reached the conclusion that bodies fall on the surface of the earth at a constant acceleration, and that the force of gravity which causes all bodies to move downward is a constant force.
- If you fall belly to earth (traditional stable skydiving position), your terminal velocity will be approximately 120 mph. If you fly head-down, for instance, and outfit yourself in a latex suit (as most speed skydivers wear), you can achieve much faster terminal speed (and acceleration).
- Falls from more than 20 feet usually result in a trip to the emergency room, but even low-level falls can cause serious head injuries, according to the American College of Surgeons. Landing on your side might be the best way to survive a fall, Hughes said. It doesn't take much of a fall to cause damage.
Updated: 25th November 2019