The 21^st Century Magazine, at South Florida's www.miami-dade-online.com.

He states that since 1978 the average passenger automobile weight has shrunk by over 1000 pounds for fuel efficiency reasons. During that period one analysis (by USA Today in 1999) determined that 46000 died in crashes they would have survived had they been in larger cars. Further, the article stated that 18% of all vehicles on the road can be classified as small cars (smaller than a Chevy Cavalier or a Dodge Neon) but they account for 37% of automobile fatalities.

That article reminded me of something I wrote about a year ago, it is as follows.

I am a bout to debunk a widely held belief.

The belief is "A small automobile will be as safe as a larger automobile if it is properly designed and equipped."

Not corrected; and I can demonstrate why it is incorrect it without restoring to any form of mathematics or any special knowledge of mathematics or physics.

Let's play a mind game.

First you must visualize two hollow spheres, one large and one small, the smaller about half the size of the larger. These spheres are made of metal and each can withstand an impact with a solid wall at speeds up to 500 miles per hour without any damage. They represent a large car and a small car of equal ability to withstand a head on collision at 500 miles per hour.

Next hang each sphere on a cord from a fixed beam so that they are just touching at their equator.

Now pull either or both of them back so that they can swing freely as pendulums.

Release them.

When they collide the larger will be slowed but not stopped and will gently return to its original position, the smaller will bounce away, and keep hitting the larger unit all of the energy it received from the impact has been dissipated. Neither will be damaged.

Now visualize a raw egg inside each sphere, not touching any part of the sphere and held in place by a perfect safety harness.

Repeat the impact demonstration. Again neither sphere will be damaged. Upon inspection neither egg shell will be broken; but the yolk inside the smaller sphere will be destroyed.

Because, as the old saying goes"It isn't the fall that hurts you, it's the sudden stop."

Both spheres received the same amount of energy from the impact, but the larger can push the other out of the way and decelerate more slowly allowing the ball, the harness and the egg to slow at approximately the same rate, the yolk may vibrate but it will not break. Not so with the smaller, it has near instant deceleration, the ball and the harness can absorb the impact energy, but at the time of impact the yolk of the egg continues to move at the speed of the small sphere until it hits the inside wall of its own restrained shell and shatters. The faster the sphere was traveling, the more damage to the yolk.

The destruction of the yolk is analogous to internal injuries.

This also explains why safety restraints can only protect the passenger up to a certain speed if the vehicle witnesses near instant deceleration.

As the two spheres approach equality of mass the differential in deceleration will lesson and at some point (depending on the speed) both yolk will be destroyed.

What this mind game demonstrates is that even if you could make a small car that would not be damaged in collision with a larger car and equip it with a superior seat belt system the passenger in the small car would be more likely to be harmed. The passenger's outer body may show few signs of injury but the internal organs will be badly damaged.

Up to a certain speed, air bags will contribute to passenger safety if they can be deployed in the path of the passengers movement at time of impact because they allow for a more acceptable deceleration. They are valuable and should be mandatory in all cars. But they cannot protect the small car passenger as well as they protect the larger car passenger.

If I haven't convinced you let's try another mind game.

Let's make the large car a railroad locomotive and the small car an indestructible sphere of the same mass as a four door sedan, mount the sphere on a set of train wheels and place in it a person in a perfect safety harness.

Put the locomotive and the sphere on the same track approaching one another at 30 miles per hour each. When they collide the locomotive will not even slow down. The sphere will experience almost instant deceleration and immediate reversal of direction. The engineer in the train won't even feel a jolt. But visualize the effect of the collision on the body of the person within the safety harness whose internal organs are moving at thirty miles an hour in one direction and are instantly reversed to travel at thirty miles an hour in the opposite direction. Will there be no harm?

At some point as the vehicles slow their speed the passenger will experience little or no harm. Speed is a factor.

But as the two vehicles approach the same mass, if they are moving at a high enough speed each passenger will be harmed. Speed is the only factor influencing passenger safety when two equally strong objects collide.

This disclosure is simplistic. That doesn't change the conclusions.

Have fun, try the mind games when the collision is not head on. I'll be the little guy still loses.

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