bstempleton@watmath.UUCP (Brad Templeton) (11/25/83)
When the first nuke blew up over Kansas City, I assume we all noticed the EMP effects - meters going off scale, power grid blowing and cars stalling. On this point I thought the film was a bit off. The electrical system of a typical car, and certainly that of a motorcycle, is very simple and based on high voltage, high current circuits. Even a big EMP would not affect this. A car with a computer controlled ignition system might die, but little else would. And certainly there would be no problems restarting them. Another note is that the car is encased in a metal box, perhaps a faraday cage against EM radiation. On the other hand, the EMP is a full-spectrum pulse from zero frequency up to x-rays, so I'm not sure what would happen here. Finally, aside from a few minor problems, and the silly x-ray effect, the movie wasn't too bad. It was just a disaster flick, and didn't seem that slanted at all. (I am not pro-freeze or pro-arms) Not worth the Moral Minority fuss. In fact, all that Jerry did was promote the viewership of the movie. -- Brad Templeton - Waterloo, Ont. (519) 886-7304
ld@hpda.UUCP (Larry Dwyer) (11/28/83)
#R:watmath:-617800:hpda:18300001:000:1431 hpda!ld Nov 27 17:10:00 1983 The very least they could have done with the electro-magnetic pulse (EMP) was to have it arrive at the same time as the flash. It seems to me that both electro-magnetic waves and light waves travel at the speed of light (or the speed of sound, or the speed of a snail, or some such thing). Of course, if Hollywood had ARRANGED it to arrive simultaneously with the flash, no one would have noticed the meter in the auto- mobile flopping to-and-fro because they would have been blinded (at least temporarily) by the brilliance of the flash. From a television point of view, this would not have made a very in- teresting shot. This demonstrates that TDA was just another at- tempt by the mogols in tinseltown to try to make a fast buck (claiming it was as accurate as possible to get everyone to watch). The EMP, which is generated in the first millisecond (or so) of the blast, is highly destructive of transistorized equipment, but automobile ignition systems should survive. It might peg the daylights out of some of the sensitive meters in a car (the ones with lots of windings), but not the entire electrical system. By the way, if it is not true that the both wave fronts would ar- rive at the same time, then someone ought to patent these faster-than-light waves and sell them to the SETI people who can use it to send messages to the stars! Larry Dwyer ucbvax!hpda!ld
henry@utzoo.UUCP (Henry Spencer) (11/29/83)
Cars with electronic (not necessarily computerized) ignitions are most
definitely vulnerable to EMP. There was at least one incident of such
cars being knocked out accidentally during EMP simulation work in the
US Southwest. Non-electronic ignitions I'm not sure about. The diodes
in the alternators might be vulnerable, although they're much tougher
parts than the control circuits of electronic ignitions.
--
Henry Spencer @ U of Toronto Zoology
{allegra,ihnp4,linus,decvax}!utzoo!henryeric@aplvax.UUCP (11/29/83)
I am not an expert on EMP, but if EMP would damage meters because of their windings, it seems to me that it would also damage the coil, wiring harness, etc. -- eric ...!seismo!umcp-cs!aplvax!eric
johnc@dartvax.UUCP (John Cabell) (12/01/83)
I'm not sure, but I think that the missile sends out the EMP
befor it hits. This is probably wrong, but that it the way
I thought it happened.
From the Deep Dark Dungeon of Cantel,
Theodrick, alias johnc
:->