Comment Of The Day: Impossible Math Edition

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Comment of the Day is awarded not just because of witty quips, sharp takedowns, and genial banter. It’s also bestowed due to advanced insights and engineering wisdom. Even if it’s not correct and makes no sense whatsoever.


Not that we don’t want correct answers, we’re just so perplexed and befuddled by this one that at this point, The Devil Drives A Mustang (Rotary Pending) is downright charming:

I checked with Jalopnik’s resident engineer, David Tracy, just to make sure I wasn’t crazy, and no, the math here is not correct. The area calculation of the pizza tin is off, and we’ve never seen a car tire that would simultaneously cover the entirety of a 12-inch pizza tin, and we’re not sure how a car would exert a downward force of 13,560 pounds unless it is an extremely heavy car. Or it has 10,000 pounds worth of pizza in the trunk (fun side calculation: how many pizzas is that?).

David’s official response:

“What we really care about more than force is compressive stress on the pizza tray, which is a pressure. That pressure is simply the force of the vehicle (which is the weight) divided by the area of the tin (this assumes the vehicle is putting all of its weight on that 12" diameter tin evenly).

Since the tin area is constant for all cases, the vehicle/elephant with the most weight will yield the most stress, and thus the thinnest pizza tray (since stress and strain are related through the Elastic modulus of the tray-a property of the material).”

Or, if we want to assume the area of contact doesn’t change whether the tank/car/elephant is stepping on the tray or just any other normal bit of ground (which is probably what we should be assuming, anyway), then it just comes down to which ever puts the most pressure on the tray. The ‘ground pressure,’ as you call it. That’s the stress.”

But still, Devil Drives A Mustang! You tried to make a good comment, and we love Good Comments around here. Be proud of your efforts. And through the Magic of Kinja™, maybe someone else can help us get the math here right, and send you off into geometric eternity.


Rusty Starship

It’s okay. The experts call this Alternative Math.