User blog:Skaffolding/Harry Potter: Belatrix creates a shockwave

Feat takes place here

Length of the great hall = 52.1208 metres

Equation for a shockwave.

(P / T^2) x (R /1.05)^5

P is air density, T is timeframe, R is radius.

Air density = 1.34375 kg/M^3.

Time = 52.1208 / 686 (speed of a whipcrack, average shockwave ) = (0.076 seconds)

(1.34375 / 0.076^2) x (52.1208/1.05)^5 = 70,113,260,326.7 joules. That's 16.76 tons of TNT, or City Block Level