Okay smart boys answer this

really hard, like much harder than anyone could throw

>>9034958
'bout tree fiddy

immidately because the man has a sever anafalactic reaction to the dust

fast enough to kill him lol are you stupid m9?

Heh, I can already see this thread is full of brainlets. Allow me to tackle this problem, OP.

Define [math] i [/math] to be the minimum speed a dust needs to be thrown at in order to kill a man.

Then, a solution is exactly [math] i [/math]. You are welcome.

Well a grain of dust weights about 1.1 x 10^13 kg/grain in earths gravity. Let's say that the minimum amount of moment you need to kill a man is a .22 cal round weighing 0.027 kg at about 1000 kph.

The speed required to kill a man with dust is
x = (0.027 * 1000) / 1.1 x 10^13 * k

Where k is the number of grains and x is in kilometers per hour

>>9035016
Correction: 1.1 x 10^-13

At a certain velocity the friction would burn away and disintegrate the dust, so rather than hitting someone with the dust you must impart enough energy into it to generate a shock wave capable of killing someone. About 20 psi overpressure and 500 mph winds at 1 meter. You'd need about 4 ounces of TNT to accomplish this which releases 500000 joules, imparting this much kinetic energy to a gram of dust would accelerate it to 70000 mph.

There are some slight inaccuracies, the TNT releases energy in all directions and the lethality of a shock wave increases in a confined space and with debris that may cause injury, but this is a reasonable upper end estimate.

I think the volume and composition of dust is more important than the speed. I mean realistically, if you have a planks length of dust, or the dust equivalent of planks length, and it was moving at the speed of light, it could go right through your body and you'd barely feel it.

Then again, a metric ton of dust, moving at just 2 MPH thrown at someone so it lands directly onto of them would bury and suffocate that person.
Or what if it's just 1 micro gram of dust that happens to be full of anthrax?

>>9034969
Fpbp

>>9035012
Best answer ITT (and I gave an answer)

>>9034958
Throwing a dust at c should be enough to kill all of man.

Now what the hell do you mean by a dust? Do you mean a dust bunny or a dust grain? What is the mass of said dust?
>>9035051
>> anthrax
Supposedly, it only takes 1-10 particles of ebola virus to infect a person. For most definitions of dust grain we can get a hell of a lot of ebola virus or even anthrax. We don't even need to throw these things we can just drop them at 0 m/s.

Also a sufficiently large dust grain made of antimatter would be enough to kill a person, which again we could throw right up at the person at 0 m/s.

So there you go OP, anywhere from 0 m/s to c.