EMP

[the guy]

For the purposes of a sci-fi story, what would be the effects of a large nearby electromagnetic pulse on a car, and what would it take to get it running properly again?

 

Thanks in advance for any help

[EdEarl]

See: EMP in Wikipedia. EMP may vary in power from a spark you get rubbing your feet on a rug, to a lightening bolt, and much stronger. I suppose one might melt a car, burn out all the wiring, fuses, and chips, or do nothing.

[the guy]

Apologies, I should have been more specific. I was meaning a pulse as might be generated by a large non-nuclear electromagnetic pulse device, such as an explosively pumped flux capacitor or the such like

[EdEarl]

A flux capacitor is fictitious; thus, I cannot comment on its properties.

 

An electromagnetic pulse (EMP) is a pulse (short burst) of photons, often having many frequencies (wave lengths), such as ones produced by sparks and lightening; although, a nuclear bomb can create an EMP that can be more powerful than ones produced by lightening. Photons carry the electromagnetic force, which includes radio waves, micro waves, x-rays, infrared, light, ultra-violet and gamma rays. I apologize for not knowing the sci-fi meaning of EMP.

[Enthalpy]

Non-nuclear weapons exist to produce EMP and have been used, for instance against Al Jazzera's transmitter in Bagdad.

 

Several methods exist. Sakharov invented the older one, where explosives compress a magnetic flux.

http://en.wikipedia.org/wiki/Explosively_pumped_flux_compression_generator

It fits in a (possibly winged) bomb.

 

More recently, semiconductor switches (and I suppose driven sparks before) enable a simpler discharge in an antenna. France and Germany cooperated on its development, but the US are often ahead in weapons, and I suspect this one already existed. They fit in a hand luggage. I'm convinced, from the observed effects, that one was used in Aoste and in one more southern city of Italy.

 

The threat is already old and very well known. Over 20 years ago, all military equipment was required to resist EMP weapons. The requirements are often disguised as "lightning"; protection implies metal housing (easy) with perfect seals (uneasy), EM-tight ventilation (uneasy), surge arresters at all cables (difficult at weak or fast signals).

 

Because these weapons exists, work, leave little clues, they are used, and are weapons of choice for secret services. I strongly advocate that airliners be protected against EMP weapons, since the disruption of the electronics at landing, even if reversible, means a crash.

 

Such a weapon was suggested to explain the car crash that killed the princess Diana - in case an external explanation were necessary. Though, I feel similar weapons that stop temporarily the brains working, probably adapted (since 1992 in France) from Transcranial Magnetic Stimulation (Wikipedia), are an easier explanation.

 

What effect on a car?

 

From a flux compressor at 10m, at least all electric circuit are destroyed, even without electronics. At several 100m, civilian electronics is destroyed. Reversible service loss of unprotected electronics must occur at maybe 1km - not quite sure.

 

A strong, unadjusted switch-and-antenna would destroy sensitive electronics at 10m and probably more, disrupt its operations at over 100m, which means a car crash because of ABS and the like. This has been demonstrated by amateurs.

 

The effect of a strong EMP on the brains is an other worry, even if the weapon is not designed specifically for that. I suppose the driver is disabled, which produces an accident as surely as disabling the electronics.

 

Other means exist, alas. Cars carry a remote control to disable them. This has been demonstrated by hackers who could use it. I may have seen it in action in France on a Peugeot-Citroën car. As usual, this foolish weakness in nations' resilience was introduced by governmental agencies in their countries; as usual, this was to improve law enforcement, safety, blah blah - and is one means more for the government's thugs to control people.

[petrushka.googol]

For the purposes of a sci-fi story, what would be the effects of a large nearby electromagnetic pulse on a car, and what would it take to get it running properly again?

 

 

 

An EMP can knock out electronic equipment for several kms from the origin. It can be produced as an aftermath of a nuclear explosion or along with certain atmospheric phenomena like lightning. (as far as i know).

 

In sci-fi (from memory) my experience tells me that alien craft (UFO's) have zapped the communication systems of pursuing interceptors (F-16's). The veracity and antecedents of these reports cannot be independently verified.

 

A model-T would suffer very little from an EMP common sense tells me. Not to mention that an upmarket Mercedes-E Class may not be left standing...

[Awesomebenc99]

if an electromagnetic pulse was caused by a sudden jolt of electricity through a transmitter of the same communication that they are using. That could make the station completely fuzzy cutting off communications. If it was strong enough it could even fry the communications system.