Throwing a plate from a third floor balcony

[femtometer]

A friend of mine was on his third floor balcony and saw someone vandalizing a wall almost directly below on the ground. He wanted to throw a plate from the balcony at the vandal.

How dangerous would this be? If each floor is about 10 ft and my friend and the vandal are of equal height, that's about a 20 ft drop, plus whatever speed he can throw the plate... I know √(2 * (20ft / 3.281ft/m) 9.8m/s^2)= 10.9m/s, but I don't know if the throwing on top of that would be seriously dangerous.

He thinks this is not a big deal but I find this reaction very concerning. I'm not sure how worried to be if another vandal ever showed up again. I wouldn't want them to get significantly injured.

 

[256bits]

Vigilanty action such as that could end up putting your friend if identified as the plate thrower, in a precarious legal situation if the vandal was seriously injured, since no other human was in danger, only the destruction of property. Better to just yell out to let the vandal know he is being observed.

 

[femtometer]

I agree of course; I've made this point repeatedly to him. I just am curious about whether my fears (about the potential for serious injury) are justified.

 

[AlephZero]

If depends on your friend. If he is any good as a baseball pitcher, or a cricket fast bowler, or a discus thrower, he could probably throw the plate at around 100 mph. The amount of damage that would cause depends on how thick the vandal's skull was, of course.

 

[sophiecentaur]

Look at the regulations about wearing hard hats in industrial situations. They are there for a reason.
If you have a vendetta with vandals, take photographs of them in action and send them to the Police. The pen is mightier than the sword (or near equivalent).