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I am bad at math... could you help me understand. A 80,000 truck and 5,000 car drive down the road... how much more damage does the 80,000 truck do? Thank you.



If the 80k truck has 5 axles (as is typical of an 18 wheeler) and a 5k car has two, then the truck has 16k on each axle and the car has 2.5k on each axle.

Because the damage scales with the 4th power, then the damage ratio is the 4th power of the axle weight ratio:

(16k/2.5k) ^ 4 = 1677x as much damage.

Edit: Sorry, that oversimplifies it a bit. For the same vehicle, the damage scales that way, but for a fair comparison, you'd have to account for the fact that the weight is distributed over more and bigger tires on each axle. Still, that should show you how the math works.




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