this post was submitted on 08 May 2025
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Fuck Cars

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[–] Landless2029@lemmy.world 16 points 21 hours ago* (last edited 15 hours ago) (1 children)

Getting hit by one of those trucks at 30 MPH has as much force as a Honda civic at 55 MPH.

Fuck modern pickups.

[–] ammonium@lemmy.world 14 points 20 hours ago* (last edited 20 hours ago) (3 children)

A Honda civic weights ~1100kg. The kinetic energy of a vehicle is proportional to v^2^. Therefore, a vehicle going at 30MPH delivering the same kinetic energy as a Honda civic at 130MPH needs to weigh in at 130^2^/30^2^*1100kg or 20tons. Modern American trucks are too big and heavy but not that big and heavy I think

[–] Landless2029@lemmy.world 4 points 15 hours ago

A fully loaded truck could exceed 10k vs a Honda at 3k. Math shows 55 mph for the Honda. A far cry from 130 mph

[–] BalderSion@real.lemmy.fan 2 points 17 hours ago

He said force, not kinetic energy. They're probably treating the acceleration term in F=ma as proportional velocity, which strikes me as naive, but it makes the math easier and it's correct if the error bars are big enough... Functionally you're comparing momentum at that point, but I imagine you can find some American truck built to evade CAFE standards that has a 4-1/3:1 weight ratio with some version of the Civic.

[–] Landless2029@lemmy.world 1 points 20 hours ago (1 children)

Either my source is wrong or memory. What's the equivalent speed for a civic going 60? Or the speed of a fully loaded truck vs a 30 civic?

[–] pahlimur@lemmy.world 2 points 17 hours ago* (last edited 15 hours ago)

48 MPH for a 3.5k vehicle vs a 9k vehicle going 30mph. The math is simple. The 1/2 goes away and it's v_2 = ((m_1*v_1^2^)/m_2)^.5. Big trucks are dangerous but don't believe everything you read.

Edit: fixed formatting