> If the helmet wasn't damaged in the crash it meant the energy was harmlessly transferred into your head.
Foam can and does distribute and absorb shock without being significantly damaged or destroyed in less severe collisions, crashes that can still put you in the hospital without a helmet.
I would maybe describe how helmets work as having a shock-absorbing cushion that slows deceleration of it’s contents. Talking about “energy” is bound to be misleading or confusing, since from a given speed, you always transfer the same amount of energy no matter how you stop, whether it’s a sudden strike against concrete or a slow gentle braking, or even waiting several minutes for air and tire friction to wear out all your kinetic energy.
I don’t want the helmet to be damaged or destroyed only because that means the crash is bad or severe.
There's much in this thread about the helmet absorbing the energy of the impact, but that's far from the whole benefit of wearing one.
The helmet, by conforming to the shape of your head, distributes the energy from the point of impact to a much larger area. So instead of having your head cracked open at the point it hits the tarmac, or pierced by a pointy rock, the force will be evenly distributed across your head.
The helmet also has a low-friction shell that will slide across a surface, which helps avoid head rotation, snapping your neck or getting whiplash, and will protect you from cuts and abrasions.
Foam can and does distribute and absorb shock without being significantly damaged or destroyed in less severe collisions, crashes that can still put you in the hospital without a helmet.
I would maybe describe how helmets work as having a shock-absorbing cushion that slows deceleration of it’s contents. Talking about “energy” is bound to be misleading or confusing, since from a given speed, you always transfer the same amount of energy no matter how you stop, whether it’s a sudden strike against concrete or a slow gentle braking, or even waiting several minutes for air and tire friction to wear out all your kinetic energy.
I don’t want the helmet to be damaged or destroyed only because that means the crash is bad or severe.