Pennies From Heaven

Most recent answer: 10/22/2007

Q:
If you drop a penny from the Empire Ste Building, would it kill a person when hitting them on the head?
- Manuela (age 40)
Florida
A:

I suspect not.  However, there are many freak accidents and under certain conditions it could possibly happen.   My own guess is that the terminal velocity of the penny would be of the order of a few 10’s of meters per second, 20 or 30 mph.  Enough to give you a jolt but not enough to kill you.   People regularly survive being pelted by penny-sized hail stones.
You can read about terminal velocity at https://www.grc.nasa.gov/www/k-12/airplane/termv.html.  
The biggest uncertainty is the so-called drag coefficient. 

LeeH


(published on 10/22/2007)