Mythbusters cannonball ‘myth-fires’

sorry it is still lack of homework

ballistics is a simple, ancient and refined art. Chamber pressures for given amounts of any type of commercial powder are all published and available. Bore size, powder charge, barrel length, projectile area and projectile mass were all known and critical to both understanding whether the breech would explode and will tell you almost exactly how fast the ball will be going when it exits the muzzle.

Once you know the muzzle velocity, barrel angle and the mass of the projectile, it's simple high school math to plot trajectory and initial impact point, minus an inch or two out because of ball friction and to the left or right depending on wind speed and time aloft. Hell, the bigger the ball the closer to mathematical ideal it gets!

A given size charge, in a given size breech, of a given powder type and set cannon dimensions will give you very similar results every time. It's not rocket science :P

hell that's what the first computers were used for, generating artillery tables. Any first year physics student should have done labs on this.

Scrapheap Challenge (Junkyard Wars) even did this-homemade cannons where points were awarded on accuracy and knockdown results to a cinderblock wall.

no one builds them like the Cheops

There are areas where brick is impractical to use (or any other heavy material) due to the composition of the ground. You can lay a foundation down, but when you're close to an underground water system and have sand for a lawn, you make due in order to live in that area. I live in South Carolina and it's usually sand or clay. We also have people living in flood zones because they decided it was a good idea to build on swampland. There was a reason it was swampland, much like there is a reason that the Misssissippi hasn't maintained the same channel over time. Really no different than when I lived in Hawaii. The colonial houses had small windows and low ceilings like their northern U.S. counterparts. It was one big heat trap. My favorite was a book on how to put out a burning woman (Victorian style clothing while cooking in said homes by a big fireplace) at one of the mission house tours.

harsh winters?

dude harsh winters all the time in the Bay Area....it gets all the way down to 33 degrees F sometimes. Harshes my buzz when I gotta go outside to smoke.

Jay, the strongest tornado recorded in the UK was no more than an F0. That's the smallest they bother to record. Typically we'll get one or two a year at most.

A minor F0 will do a little bit of damage. Suck off a few tiles, blow over a wall maybe.not much more.

Now, think about how many tornadoes the US gets in a year. Most of those will be greater than F1, and a good (and dangerous) number will be F5, the quarter-mile wide monsters that destroy everything in their path. An F5 would turn a brick terrace into a neat pile of rubble on the other side of the street, turn every tree on the road upside down and pile all the cars on top of each other just for fun.

Compare like with like.

Now, as for why we use brick, I'll tell you: weather and resources. We're a wet country and we have lots and lots of clay, whereas the south-western united states is a dry country that has lots of timber. In cool, wet environment the most appropriate materials are those that keep out moisture, require little maintenance to avoid rain damage, and which still provide decent insulation. Brick fulfils all three requirements very well.

Having experienced tornados twice in my life in the southern US, I assure you that not all tornados are created equal. Only an underground bunker could possibly have survived the F5 that went through Birmingham, Alabama. After all, it isn't the wind speed in excess of 350 km/h so much as the minivan striking the house at 150 km/h.

Former Brick-loving South African...

Which I am. Turns out that in the US, sky-scrapers are built out of steel and the masonry is cladding. Steel flexes nicely and withstands quakes. In downtown Seattle in the pissy little 6.8 Nisqually quake, all of the old brick buildings rained their bricks down on the streets. They don't build those anymore.

Smaller buildings might be reinforced concrete, but never brick, except as cladding.

Now it's still a puzzle to me why Floridians build with wood. That's just economics. You used all your wood to build ships to form an empire.... thanks for that BTW as one of the remnants.

@Boltar

What are you on about?

You've forgotten (or never heard of) the great San Francisco earthquake of 1906. The city was built almost entirely of brick, and the earthquake transformed it into a huge heap of rubble.

Current large buildings on San Francisco are NOT simply concrete... They have massive steel internal reinforcement and rest on foundations composed of metal springs, or on rollers to permit the building to withstand earthquakes of as much as 8 on Richter's scale. As you might imagine, this is very expensive and not practicable for houses.

Indeed wood frame houses are as safe as , well, houses in a actively seismic area. Construction of houses in California requires the use of plywood or Oriented Strand Board (OSB) sheathing with specific metal reinforcement as stiffening for the frame. The State studies the effects of major earthquakes on various construction methods, and the cannonballed house's construction was no doubt appropriate for the regulations in effect at the time of construction.

Pray your massive brick walls never encounter a good shake test!