f = ma. The bus is considerably more dangerous than a car, even while traveling at a significantly lower speed. As the parent comment noted, there are certainly some aggressive bus drivers out there as well.
Actually neither of those matter much anyway. The energy transferred is primarily a function of the velocity difference (squared) and the mass of the lighter of the two objects. That is, a pedestrian will experience a collision with a car and with a bus in much the same way.
If the two objects are close to the same mass, i.e. car vs. car, the energy transfer will be reduced by up to 75%, but otherwise the mass of the larger object is immaterial. That is, a car-car collision at 60 MPH does equal damage as a bus-car collision at 30 MPH.
This is correct. My grandfather was a physicist who reconstructed some of the nastier accidents in CA. He was always looking for two values for most situations: delta-v, and (mv^2)/2. The 'v' being the delta-v of the two vehicles when they collided. The damage done will generally be a function of the kinetic energy that hit it.
Note that this implies that unless there are other dangerous road conditions (fog, ice, etc), the safest speed is "the same speed as everybody else" so the delta-v is minimized.
Fun note for HN: he had software built for DOS that I helped him get running in dosbox so he could run it on a modern computer. It would reconstruct the motion of the vehicles from the final resting positions and the depth of the dents. working backwards from the implied kinetic energy. Apparently the DOS version was a port of his original FORTRAN source... on punch cards.
The bus is considerably more dangerous than a car, even while traveling at a significantly lower speed.
The potential damage may be greater, but significantly lower speeds creates a much greater risk of some accident. All things considered, then, it's not clear what's worse at the bottom line.
f = ma. The bus is considerably more dangerous than a car, even while traveling at a significantly lower speed. As the parent comment noted, there are certainly some aggressive bus drivers out there as well.