Well, HPE, and not for much longer (going out on my terms)... anyway - we used to get ink for free, before the split last November, but honestly, I stopped using my HP printer about a year before that. The scanner functionality didn't work right over the network and after getting a Dell (the horror) color laser, there was no reason to print on an inkjet anyway. Now I have an All-in-one that prints great color and scans, all over the network - even does AirPrint and an app to print over Android devices, too.
Regardless of my feeling toward Meg Whitman and destruction of HP, I'd still recommend never buying HP Inkjets - same as I recommend not buying Epson (had those for years, then they put in a self-destruct after 3000 prints that just printed garbage on your media, dumb and expensive to the user).
The tactics of these companies are reprehensible, and should not be supported by anybody. It's not like HP cares about its customers any more, anyway. It's all about stock prices so they can sell it all off to hedge funds (and devalue the middle class' pension funds to line their own pockets) just before it finally collapses.
There are a number of launchers that burn the same engines from ground to true vacuum.
Trade offs were made. Those nozzles are only performing optimally at one altitude. I didn't say it can't be done, it's just not efficient.
The F-1 was actually optimised for reliability and not-killing-the-passengers hence its abysmal performance by today's standards.
I believe GP was referring to aerostatic nozzle optimization, which every rocket needs to have. This type of optimization applies only to the nozzle, and not the rest of the rocket engine. (pumps, combustion chamber, etc.) A rocket with a nozzle designed for space will not perform well compared to the same rocket with a nozzle optimized for earth at sea level. This is because Earth's atmosphere plays a role in how the gases expand from the engine.
This phenomenon can be observed particularly well on the SpaceX webcasts. The exhaust gases from the engine are expelled directly behind the engine when the rocket is leaving the launch pad. Just before stage separation though, a significant portion of the exhaust gasses can be seen to the sides of the rocket. This is another of the many reasons multiple stages are used in rocketry.
Other trade offs are made between safety and performance, mainly in the combustion chamber and pumps. Experienced scientists and engineers can do some calculations to factor out nozzle optimization and get a more accurate comparison between different types of rockets.
I would agree, that is far worse of an automated weapon. The SK turret requires human authorization before firing.
150 deg F is not the same thing as 180+ that the expert said will cause "full thickness burns" also, scald is not third degree, but first degree burns.
Ok, so you are thinking you will lose less hydrogen than the equivalent charge of a battery? You sound like you don't know anything about the issues involved.
Power source > hydrogen > storage > fuel cell > battery
is better than
Power source > battery
in your mind? Somehow using power to crack hydrogen and store it, then run it through a fuel cell to charge a battery is infinitely more efficient than just charging the same damn battery?
In 6 months worth of storage ALL the Hydrogen would escape....I'll take the 2-3% of batteries any day over 100% for H2.
Do we somehow need to be to understand that H2 is not available free from any source?
H2 is produced currently by cracking natural gas (Methane), so it is a process which produces lots of CO2, and it is a process that would be better just put on the train. Wouldn't it be better to use the Methane to power the train directly? It has a higher energy content than the produced Hydrogen after all.
Where did the poster say the power plant needed to be on the train? As far as I see, that is only something being added as a strawman argument.
Happiness is a hard disk.