Plausible Impact Energy of a Small Meteroid?

[Pgeske]

Could someone please give me a plausible impact energy of a very small (maybe .1 or .2 meters diameter) meteoroid hitting the earth. This does not need to be exact at all. I just would like an extremely rough estimate of a possible energy of impact. For example, larger meteoroids (i.e, 7-8 meters) can impact with kilotons of TNT. How about small meteoroids? Thanks.

 

[cragar]

well the impact force would be F=dp/dt the change in momentum divided by the impact time. Where the impact time would be small and tricky to measure.

 

[Filip Larsen]

Technically you can calculate the kinetic energy of an asteroid if you know its impact speed and mass, or instead of mass, density and size. All of this energy is released on impact, but for small meteoroids all or most of this energy is released to the atmosphere.

To get an average number you can perhaps look at the Torino impact hazard scale where a 1 km asteroid is equated to an energy release of 10⁵ MT. Since energy content scales with the cube of the size of the asteroid a small asteroid at 0.1 meter size would then have 10^-12 times that much energy which is around 10^-8 MT, 10 kg of TNT, or 43 MJ.

Note that this may not be a valid number, since the Torino scale seems to be applicable mainly for asteroids of sizes above 20 meter.