Quote:
Renegade 13 said:
Personally, I'd much rather be driving some 1970's-1980's car than a newer car. Why? The metal content. Sure, the plastic car and the metallic car may have similar strengths, etc. But everyone's failed to take into account a very important aspect; inertia. In a heavier vehicle, you will stand a much better chance of survival in the event of a collision with another vehicle, simply due to inertia.
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With all the science people on these boards, nobody's called bull**** on this yet? The weight of the vehicle does NOT increase the safety. If anything, extra weight makes car more dangerous.
You should recall from Newtonian physics, that inertia is the tendancy of mass to remain at it's current velocity (or speed and heading, if you prefer). When the vehicle is moving, the inertia causes it to keep moving at its current speed until outside forces slow it down. In a wreck, this outside force is applied during a fraction of a second. So, the equation for kinetic energy, E=(0.5)*m*(v^2), says that a vehicle that is twice as heavy will have to withstand twice as much energy on impact. With older cars, the extra weight does not add to the structure of the vehicle overall, and simply adds on to the stress the frame needs to deal with to protect the occupants of the vehicle.
Plastic bumpers, you say? They spread out the time of impact, as the bumper crumples up, absorbing a good percentage of the impact energy. With a metal bumper, there isn't really that much crumpling; it just turns into a metal bar that rams into the frame. The frame of the car would probably deform a metal bumper just as much as the impacted object would in a major crash.
For another way to look at it, think of egg drop contests. You go up to the roof of a moderately tall building (say, between two and four stories), and see what kind of vehicles will allow an egg dropped from that height to not crack. People come up with all sorts of schemes to protect the egg, and most involve either some kind of parachute (reduced speed of impact) or some kind of larger hard shell. But the killer in impact situations is all of the energy is dispersed in a short time period. The trick is to get the decelleration to take as long as possible. The impact can be half the speed of what it would have been without a parachute, and the outer structure could take a lot of energy, but the egg would still break if the decelleration time is 0.001 seconds. But spread out the time to 0.1 seconds, and the egg is intact. That is the route to go for safety.
*/end hijack*