User blog:ThePerpetual/Request 12: A Horse Explodes Several Other Horses

"I looked around at the rubble. Blowing up the three alicorns with a balefire egg was delicious overkill. One of them had even been fast enough to get her damned shield up before I could fire. Didn’t help one damned bit. But I had been unprepared for how big the explosion would be. I’d been cautious, aiming for the wall behind the alicorns. That wall was no longer there. Nor was the floor or ceiling. The room that the alicorns had occupied, as well as the rooms to each side, had become a gaping maw open to the rain. I had fired and dived back behind the wall. That wall had blown into the hallway, collapsing, trapping me between it and the other. I checked the medical assist spell and was surprised to find that, while battered and bruised, nothing was broken. I was lucky that I wasn’t a smear."

Source: https://pastebin.com/NEDtYPPx

So uh, I've been informed that this happened inside of a police station- specifically, on the second of four floors. Clearly, the room was also adjacent to the building wall that it blew in, since said wall led to the outside where it was raining.

Here, as you can see, I've put together a picture gathering measurements I'll use for this calculation. A low end will simply be destroying a single room, since technically speaking that does leave a "hole" in the adjacent rooms, for lack of their own wall/floor/ceiling. The high-end will instead use the mass of all of these walls, multiplied by five (three rooms in each direction from the wall, plus one overhead and one below since it's the second floor.) Technically, each of these extra rooms should be missing one wall/floor/ceiling, but this shockwave is a sphere: i.e. it's also blowing away a bunch of matter in the corners of the blast wave. Right? And the mid-end will just be the average of the two.

Now, for the amount of wall getting busted:

27 px = 1.75 meters (Avg. human)

1.75 m / 27 px = .0648 meters/pixel, or 6.48 centimeters/pixel, or 272.1 cc/cubic pixel

Volume: ((73.79 * 66.64 * 41) = 201611.99 px^3) - (((73.79 - (5.39 * 2)) * (66.64 - (5.39 * 2)) * (41 - (5.39 * 2))) = 106366.50 px^3) = 95245.49 px^3, or

95245.49 * 272.1 = 25916297.829 cubic centimeters of wall.

This was heat based, which leads me to believe this was probably vaporization. Time to bust out E=m*c*ΔT again

(Assuming from now on that the walls are clay, more specifically brick)


 * Boiling Point of Clay Brick (ΔT + 23): | Apparently 9000 Celsius this was a mistake aaaa
 * Specific Heat of Clay Brick (c): | 920 Joules/kg*K
 * Density of Clay Brick: | ~2.0 grams/cubic centimeter (or 2000 kg/m^3)
 * Latent Heat of Fusion for Clay Brick: | 2258000 Joules/kg
 * Enthalpy of Vaporization for Clay Brick: ??

Let's just find the mass values, I guess

Low-End: 25916297.829 * 2 = 51832595.658 grams, or 51832.595658 kg

High-End: (25916297.829 * 5) * 2 = 259162978.29 grams, or 259162.97829 kg

Mid-End: (((25916297.829 * 5) + 25916297.829) / 2) * 2 = 155497786.974 grams, or 155497.786974 kg

Which yields...


 * Low-End: (51832.595658 * 920 * 8977) + (51832.595658 * 2258000) = 5.45115e+11 Joules, or 130.29 Tons of TNT
 * Mid-End: (155497.786974 * 920 * 8977) + (51832.595658 * 2258000) = 1.63535e+12 Joules, or 390.86 Tons of TNT
 * High-End: (259162.97829 * 920 * 8977) + (51832.595658 * 2258000) = 2.72558e+12 Joules, or 651.43 Tons of TNT

...what the actual hell

Why is vaporizing brick so hard

Though our PoV character Littlepip didn't get smeared, they were caught in the blast radius/trapped under the rubble that didn't just go up in a puff of smoke, apparently.

Even if we assume she's an entire room width (66.64 pixels, or ~4.32 meters) away from the edge of the blast in each case (for a total distance of 8.64/10.8/12.96 meters for each end, roughly), she'd have withstood what of the shockwave went through whatever wall she was behind.

| Apparently, this exists... the average weight of a pony | is 500 lbs (or ~225 kg), and all sources I've seen estimate the MLP-style ponies are also about 4 feet at the shoulder, so I can use that to get ~4.3 square meters of surface area on Littlepip, or ~2.15 meters struck out of the (938.07, 1465.74, or 2110.67) square meters of blast area.

So, for Littlepip's Durability,
 * Low-End: 5.45115e+11 * (2.15/938.07) = 1.24937e+9 Joules, or 0.299 Tons of TNT.
 * Mid-End: 1.63535e+12 * (2.15/1465.74) = 2.39879e+9 Joules, or 0.573 Tons of TNT.
 * High-End: 2.72558e+12 * (2.15/2110.67) = 2.77637e+9 Joules, or 0.664 Tons of TNT.

Didn't even break anything, just some bruises.

...I just

This is probably wrong

I'll come back and try again with the values for stone instead of clay brick, probably, those sound more likely to make sense

Final Results?
Balefire Egg
 * Low-End: 130.29 Tons of TNT
 * Mid-End: 390.86 Tons of TNT
 * High-End: 651.43 Tons of TNT

Not Becoming A Bloody Mess
 * Low-End: 0.299 Tons of TNT
 * Mid-End: 0.573 Tons of TNT
 * High-End: 0.664 Tons of TNT