The ‘kei’ cars and trucks are growing in popularity in the U.S. But many states have explicitly banned them in recent years. A bill at the statehouse would allow them on Colorado roads.
A Honda civic weights ~1100kg. The kinetic energy of a vehicle is proportional to v2. Therefore, a vehicle going at 30MPH delivering the same kinetic energy as a Honda civic at 130MPH needs to weigh in at 1302/302*1100kg or 20tons. Modern American trucks are too big and heavy but not that big and heavy I think
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.
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_12)/m_2)^.5. Big trucks are dangerous but don’t believe everything you read.
A Honda civic weights ~1100kg. The kinetic energy of a vehicle is proportional to v2. Therefore, a vehicle going at 30MPH delivering the same kinetic energy as a Honda civic at 130MPH needs to weigh in at 1302/302*1100kg or 20tons. Modern American trucks are too big and heavy but not that big and heavy I think
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
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.
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?
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_12)/m_2)^.5. Big trucks are dangerous but don’t believe everything you read.
Edit: fixed formatting