Any good final-year engineering or physics student could make a gun-type bomb and expect it to work first time.

The other reason Nagasaki had fewer casualties was that the bomb didn't ignite a firestorm. There were still fires of course, but not the kind of raging inferno that creates it's own tornado to feed itself. This is despite the higher yield of the second bomb.

They were trying to avoid unconditional surrender, i.e. they wanted to guarantee the survival of the emperor*, even if without power. They eventually surrendered when they were allowed this. The main things that caused Japan to surrender when they did were 1) The USA finally backing down on "unconditional" and 2) the threat of imminent Soviet invasion. That Soviet threat was the cause of 1) - the USA didn't want Japan to be occupied by the USSR.

If you read the minutes of the Japanese meetings when surrender was debated they atom bomb is barely mentioned, the vast Soviet army and the fate of the emperor dominated those discussions. The atomic bombs were no more destructive than the incendiary raids that had already caused Dresden-type firestorms in many Japanese cities.

*Westerners struggle to understand this, in a country where the emperor is worshipped as a living deity his execution for war crimes would have been seen less like hanging Harry Trueman and more like the crucifixion of Christ.

There are moulding processes that are economical from a few tens of units. Mostly these involve making soft moulds from 3D printed forms and the moulds are good for perhaps 50 units each. They are slower though so if you want a hundred units quickly it might be better to print, and just contract out to multiple printing places if you need extra capacity to speed it up.

I haven't worked on anything newer than about 10 years old but every fuel-injected petrol engine I've played with has had a mechanical butterfly valve operated by the pedal. The fancy electronics then measures mass flow rate (which is a function of throttle plate position, air temperature, air filter condition, engine rpm, etc) and injects the right amount of fuel. It's not *that* different from a mechanical carburettor except that carburettors measure volumetric flow and have to be tweaked for summer/winter to account for the different air inlet temperature

Where I'm from (UK) nearly everyone has a manual transmission :-)

Natural gas is generally pumped around by turbines burning natural gas, it's cheaper but also happens to be immune to electrical problems. Failure of controls cause valves to stick in their last commanded position though so expect at least some problems with pressure fluctuations, etc.

Taking a 240V +/- 6% country and making it a 230V +10%/-6% country whilst not making any changes to the actual supply voltage doesn't sound all that much like a success story. (220V countries became 230V +6%/-10% and all new devices are designed for 230V +/-10%)

This. I wouldn't go as far as Sowelu but an extra few mm of thickness (say up to a max of 15mm) for a greatly increased battery life would finally convince me to get a smartphone.

I find the idea of changing materials part-way through a piece interesting, you might not be able to fuse them but I'm imagining something similar to a dovetail joint, printed in place and utterly permanent. Essentially just mechanically interlocking the different materials during printing.

That's exactly what the spiral arms are, they can't be the same stars orbiting together in that shape as that would imply a rigid body rotation. The situation where everything moves around together as if it were nailed to a rigid cosmic disc doesn't work because the orbit time of the stars at the centre of the galaxy is less than that of the stars at the edge. This is a consequence of the orbital physics, it's essentially the only way the forces can balance.

So, the stars in the centre whiz around quickly (in cosmological time anyway) whilst the ones at the edge take forever. The spirals are simply areas of higher star density but they are not the same stars all the time. This region does rotate but more slowly than the stars contained within it. So, why are there areas of increased star density? No-one's entirely sure but it seems likely that these are actually regions with higher rates of star formation, with many young, short-lived blue stars.

80 kg of water is 0.08 m^3 (1 litre of water being a cube 0.1 meters each side and of mass 1kg), if you turn it into steam it expands by about 1700 so assuming atmospheric pressure gives 0.08*1700= 136 m^3 of steam as the OP stated.

This is clearly an agent who has never been to a beach. You don't even have to sit down and it'll be everywhere.

This is well known to be possible, has been done for years, and you can buy commercial test equipment that sends spoof GPS signals (for testing GPS receivers obviously). More importantly there's another simpler way that cannot be dealt with by signing - just relay GPS signals from elsewhere.

If you capture GPS data at a point in space and retransmit the whole lot with enough power that the receiver sees only your signals then the receiver sees all the same phase relationships that put it in the location where you captured the data. It has no way of knowing it's been delayed by a few microseconds and signed GPS signals would look perfect. The only way around that is to compare it with inertial navigation, loran, etc or perhaps to have a very accurate clock on board to try and spot the extra delay.

Like you I'll not worry about it until I get a car with some silicon in it. It does have two germanium transistors in the tachometer though, maybe I should be worried :-P

Why be ashamed of it?