tminus7700

tminus7700 t1_j621s1g wrote

Reply to comment by Minuted in TIL that World War II Spitfires only had about 20 seconds of 'gun time' before running out of ammo, making most movie depictions wildly inaccurate by TimmyIsBaller

> But undoubtedly far less than 10 percent of all rounds fired connected with a target

I've heard far, far less than that. https://history.stackexchange.com/questions/1711/number-of-bullets-used-in-ww2

>The number of bullets fired per kill varies based on the source from 5k to 50k.

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tminus7700 t1_j61x9o8 wrote

Reply to ELI5: How is donating equipment to participate in war, not considered going to war? by lloyd705

One historical precedent was the Lend-lease act.

>In December 1940, Roosevelt introduced a new policy initiative whereby the United States would lend, rather than sell, military supplies to Great Britain for use in the fight against Germany. Payment for the supplies would be deferred, and could come in any form Roosevelt deemed satisfactory.

Basically we are just a material supplier. As long as we don't actually use our own troops to fight, we are not really "in the war". We are no different that those many other countries that supply medicine, fuel, food and other supplies.

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tminus7700 t1_j236y0c wrote

Reply to comment by Redshift2k5 in ELI5: What is yellow cake uranium? by Any_Potato8193

> It's a powder form of purified uranium

It is not purified uranium. It is uranium oxide. Before being reduced to the metal.

https://en.wikipedia.org/wiki/Yellowcake

>Yellowcake (also called urania) is a type of uranium concentrate powder obtained from leach solutions, in an intermediate step in the processing of uranium ores. It is a step in the processing of uranium after it has been mined but before fuel fabrication or uranium enrichment.

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tminus7700 t1_j23512v wrote

Reply to comment by hidrate in Drilling into concrete wall questions by Sleepy_C

Yes. I have found that you can drill into a rock in the cement. The rock is often much, much harder than the cement. And that will greatly slow down a typical carbide drill without hammering.

Also be very sure the wall is not pre-stressed concrete. If it is you can severly compromise the structural strength. My daughter bought a fairly new house in Las Vegas. The garage floor is pre-stressed concrete and has a warning molded into the front main florr near the door that says to not cut or drill into it.

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tminus7700 t1_iykl7q5 wrote

Reply to comment by somedave in New device can make hydrogen when dunked in salt water by TurretLauncher

That is key. From what I have read this is NOT a hydrogen producing device, but an enhanced reverse osmosis device. That provides water to a conventional electrolytic cell. You could just electrolysis sea water directly. You will get hydrogen and chlorine. I don't know which would be more energy efficient. The chlorine would also be a useful product.

Besides hydrogen is not close to the fuel of the future.

>Water electrolysis has not yet been implemented on a large scale >Only four per cent of all hydrogen produced worldwide are the result of water electrolysis. As the electrodes used in the process are not efficient enough, large-scale application is not profitable. **To date, hydrogen has been mainly obtained from fossil fuels, with large CO2 volumes being released in the process,**says Wolfgang Schuhmann. "If we succeeded in obtaining hydrogen by using electrolysis instead, it would be a huge step towards climate-friendly energy conversion. For this purpose, we could utilise surplus electricity, for example generated by wind power."

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tminus7700 t1_itt7m63 wrote

Reply to comment by EndlessEmergency in TIL that flight recorders must be able to withstand an acceleration of 3400 g for 6.5 milliseconds and that this is roughly equivalent to an impact velocity of 270 knots (310 mph; 500 km/h). by IchBinKoloss

I worked in the ordnance industry. We had to design warheads and electronics that could withstand 60,000g's for 20 milliseconds. These were used in "hard target warheads". Ones that had to penetrate a reinforced concrete bunker and still function properly. You can engineer things to with stand virtually anything. The physicist Lew Allen, in the 1950's experimented with getting steel balls to survive within the nuclear fire ball of an A- bomb blast.

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