During a head on collision between two automobiles, the occupants are decelerated rapidly. use the idea of work to explain why a air bag that quickly inflates in front of an occupant reduces the likelihood of injury.

The work done to stop a car during collision is described in the equation W = F * d where F is the force of collision and d is the distance of impact. In this case, when work is constant and the distance is long, then the force must decrease. If the distance shortens, then the force of collision must increase. The inflation deflation process of the airbag lengthens the distance, hence force is lessened.

An  atom  (ours, not carroll's) consists of a positively charged  nucleus, surrounded by one or more negatively charged particles called  electrons. the positive charges equal the negative charges, so the atom has no overall charge; it is electrically neutral. most of an atom's mass is in its nucleus; the mass of an electron is only 1/1836 the mass of the lightest nucleus, that of hydrogen. although the nucleus is heavy, it is quite small compared with the overall size of an atom. the radius of a typical atom is around 0.1 to 0.25 nanometres (nm), whereas the radius of a nucleus is about 10-6  nm.  *  if an atom were enlarged to the size of the earth, its nucleus would be only 200 feet in diameter and could easily rest inside a small football stadium.read more on -