Should USA be seriously concerned about N Korea now?

[Nagel]

30,000 feet is a pretty normal height for an airliner to fly. A nuclear blast at that height would wipe out London, spread radiation over the whole of southern England and knock out most electrical appliances incliding computers over a similar area. I think a terrorist group would be satisfied with that.

 

To put this in context. We visited Mount St Helens years after it erupted. Every tree within 15 miles of the eruption had been flattened and was pointing away from the blast. I imagine a nuclear exposion just 5 miles up would be capable of flattening any building down below. I'd certainly not want to be around down there telling them they had got it wrong.

 

What size nuclear weapon are you supposing? If you let me know I'll work it out with my cold-war nuclear bomb effects slide rule.

 

I actually have one of these (and the book) - https://www.orau.org/ptp/collection/sliderules/nucbombeffcompbig.htm

[tzijlstra]

I think a terrorist group would be satisfied with that.

 

And since when is North Korea a terrorist group? Or is that irrelevant in the context of your right wing fear-mongering?

[apelike]

Would it cause more nationwide electrical devastation due to magnetic pulse damage at a greater height?

 

I doubt it as the EMP would be weaker the further away it is from its target due to the inverse square law. Electrical devastation is mainly due to the EMP travelling along overhead wires more than anything else. Around 1500 to 2000ft is what a modern air-burst nuke would detonate at to give it maximum ground damage.

[foxy lady]

What size nuclear weapon are you supposing? If you let me know I'll work it out with my cold-war nuclear bomb effects slide rule.

 

I actually have one of these (and the book) - https://www.orau.org/ptp/collection/sliderules/nucbombeffcompbig.htm

 

Ah good. Did you advise Bin Laden what sized aircraft he needed to bring down the twin towers.

 

---------- Post added 10-04-2016 at 23:30 ----------

 

And since when is North Korea a terrorist group? Or is that irrelevant in the context of your right wing fear-mongering?

 

There are terror groups spring up and obtain support from regimes all around the world despite your islam excusing snivelling. Why some of your mates took over half of Syria along with all the weapons they captured. It's good to see the Russians have killed rather a lot of them.

Edited April 10, 2016 by foxy lady

[Penistone999]

Step by step North Korea is completing the tasks needed to have a nuclear-tipped missile capable of striking the US.

 

In recent weeks, it has said it has made the heat-resistant materials necessary. It broadcast pictures of Kim Jong-un looking on approvingly at what it claimed was a small nuclear warhead. Now it says it has the necessary rocket engine.

 

It is impossible to verify the claims, though on Tuesday the South Korean government accepted that North Korea had made crucial advances

 

Bearing in mind the unstable mentality of the N Korea leader, should the US be serious concerned?

 

He would need to have a death wish if he fired a nuclear misslie at America.

 

He may have developed a few toys , but the Yanks have much bigger Nuclear toys and would blow his little tinpot country off the face of the earth if Kim attacked them.

[Obelix]

I doubt it as the EMP would be weaker the further away it is from its target due to the inverse square law. Electrical devastation is mainly due to the EMP travelling along overhead wires more than anything else. Around 1500 to 2000ft is what a modern air-burst nuke would detonate at to give it maximum ground damage.

 

High altitude is more effective for an EMP.

 

The EMP doesnt travel along electrical wires. IT's cause by gamma radiation from the explosion inoising the atoms in the atmopshere - you end up with an exceedingly high but brief pules of electrons travelling at near light speed. These cause a field strength of many kilovolts per meter in the air - this is enough to induce large currents in transistors and blow them, regardless of what they may or may not actually be connected to.

 

---------- Post added 11-04-2016 at 00:50 ----------

 

He would need to have a death wish if he fired a nuclear misslie at America.

 

He may have developed a few toys , but the Yanks have much bigger Nuclear toys and would blow his little tinpot country off the face of the earth if Kim attacked them.

 

And you think China with it's much larger and truly inter continental missiles are just going to sit back as a large glassing of their next door neighbour take place?

 

They wont know where the missilsa re going to start with. Just that they are "inbound".

 

---------- Post added 11-04-2016 at 00:52 ----------

 

At 30 000 ft, much of the blast would be wasted disrupting the upper atmosphere and beyond.

 

The Japanese bombs were detonated at about 1500ft during WWII. I'm sure that modern weapons will be suitable for detonation at a higher altitude, but not by a factor of 20.

 

I'm fairly sure that Foxy will blame Jeremy Corbyn for this failiure of Physics, but in reality, she only has herself to blame for her rhetoric and hyperbole.

 

Depends on the warhead size. A table here gives me an ideal burst height of 6800 feet for a "typical" 300kT city killing weapon.

 

Hardened targets like bunkers are groundbursts, or even penetrating underground bombs.

[apelike]

High altitude is more effective for an EMP.

 

The EMP doesnt travel along electrical wires.

 

It does when it reaches the lower atmosphere and near the ground and the effect is caused by induction which cause a fast surge or "spike" and the reason why surge protectors are use in IT equipment. Its also the reason why brown outs have occurred several time in the USA and Canada due to a similar effect from solar eruptions and electrical storms. The wires act like an aerial, pick up the disturbance and distribute it at high speed.

 

IT's cause by gamma radiation from the explosion inoising the atoms in the atmopshere - you end up with an exceedingly high but brief pules of electrons travelling at near light speed. These cause a field strength of many kilovolts per meter in the air -

 

That is true but high altitude EMP's stay at high altitude and generally do not travel into the lower atmosphere. They can knock out satellites and maybe plane electronics but not much else.

 

this is enough to induce large currents in transistors and blow them, regardless of what they may or may not actually be connected to.

 

I think you will find that as being a bit of a myth and a bit like the idea that it will render cars immobile by destroying car electronics. Large current can only be induced if there is a large enough conductor supplying the transistor for the current to flow through. Most sensitive electronic items are also screened by a metal surround which acts as a Faraday cage so are difficult to damage that way. Surges travelling in the power wires have the most damaging effect.

[tzijlstra]

Ah good. Did you advise Bin Laden what sized aircraft he needed to bring down the twin towers.

 

---------- Post added 10-04-2016 at 23:30 ----------

 

 

There are terror groups spring up and obtain support from regimes all around the world despite your islam excusing snivelling. Why some of your mates took over half of Syria along with all the weapons they captured. It's good to see the Russians have killed rather a lot of them.

 

Haha, comedy gold, keep it up!

[Dr Afzal]

Anyway further to my original post from 10 months ago it`s starting to warm up a bit now that there is finally a President with big enough balls to take some action.

 

President Donald Trump will be forced to deal with ongoing threats from North Korea as that country gains the ability to threaten the continental U.S. with a nuclear strike, an official said on Sunday, hours after Pyongyang fired a ballistic missile into nearby seas.

 

12th February 2017

https://www.bloomberg.com/news/articles/2017-02-12/north-korea-fires-unidentified-missile-s-korea-military-says

[apelike]

From that same link:

 

"The U.S. Strategic Command said in a statement that Pyongyang launched a medium- or intermediate-range ballistic missile that posed no threat to North America."

 

Given the hype created I bet the arms manufacturers can wait for a conflict.