2.7 Momentum & Safety

If you drop an expensive mobile device onto a cement sidewalk, you might be disappointed if it no longer works, but at least you can have it repaired or replaced.  If you hit your head on a cement sidewalk, the long-term consequences could be much more serious.  Although medical science has learned a lot about the workings of the brain, only so much damage can be repaired, and, unlike your mobile device, an off-the-shelf replacement for your brain is not possible.

People who are exposed to hazards that could lead to head injuries and possible brain damage should take protective measures while at work or at play -- they should wear helmets.

When worn during an accident, like a fall from a bike or being hit by falling lumber, helmets increase the length of time of the collision thus decreasing the force experienced by the person's head.