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GeneralRe: Visual Studio 2015 release today Pin
Kornfeld Eliyahu Peter20-Jul-15 0:51
professionalKornfeld Eliyahu Peter20-Jul-15 0:51 
NewsHow to find career happiness: Stop chasing the money Pin
Kent Sharkey19-Jul-15 18:08
staffKent Sharkey19-Jul-15 18:08 
NewsWhat makes a great developer? Pin
Kent Sharkey19-Jul-15 18:07
staffKent Sharkey19-Jul-15 18:07 
GeneralRe: What makes a great developer? Pin
PIEBALDconsult19-Jul-15 18:42
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GeneralRe: What makes a great developer? Pin
TheGreatAndPowerfulOz20-Jul-15 5:24
TheGreatAndPowerfulOz20-Jul-15 5:24 
NewsThis company aims to launch rockets with beams of power Pin
Kent Sharkey19-Jul-15 17:42
staffKent Sharkey19-Jul-15 17:42 
GeneralRe: This company aims to launch rockets with beams of power Pin
Daniel Pfeffer19-Jul-15 19:12
professionalDaniel Pfeffer19-Jul-15 19:12 
GeneralRe: This company aims to launch rockets with beams of power Pin
enhzflep19-Jul-15 19:21
enhzflep19-Jul-15 19:21 
Hope nothing goes wrong, lest it makes directed energy take-downs of missiles look like a sparkler compared to a fireworks display.

I'm sceptical about the ability to beam sufficient power from a 1km² antenna to the heat exchanger on a rocket moving as fast as it will be. I'm also more than a little dubious about the author's understanding of the reasons that we have multiple-stage rockets in the first place - they're far more efficient than single-stage ones, for two reasons. Only one of which applies to liquid fuelled rockets.

Firstly, if you split the fuel into two tank/motor assemblies you can get rid of 1/2 of the total fuel tank weight after you jettison the first stage, you also lose some of the length, which improves the rocket's Cd. Admittedly, you need to carry several engine modules for a liquid fueled motor and the associated stage couplings, or an extra nozzle for solid fuelled ones, but the penalty of either of these is outweighed by the reduction in weight of everything that was dumped after stage-burnout.

Secondly, and not important here - if you multi-stage solid-fuel rockets, the fuel in your second stage will produce more peak thrust and specific impulse than it would if it were in a larger single stage. Why? Simple, the solid fuel is housed within the reaction chamber. As the fuel burns, the volume inside the chamber increases which leads to lower pressures, which then leads to slower burn-rate, that further decreases the pressure in what is a vicious cycle.

This can be seen in any number of commercial multi-stage rockets of the 'small' variety. The infamous BUK is multi-stage, yet it has an operational ceiling of just 22,000 meters. To send it as high with a single stage would cost and weigh more. It would also be detrimental to the missile's maximum velocity.

This is such simple and basic stuff. I'm rather bemused by the fact that my standard retort in such a situation is entirely invalid, since this actually is rocket science.
"When I was 5 years old, my mother always told me that happiness was the key to life. When I went to school, they asked me what I wanted to be when I grew up. I wrote down 'happy'. They told me I didn't understand the assignment, and I told them they didn't understand life." - John Lennon

GeneralRe: This company aims to launch rockets with beams of power Pin
Dan Neely20-Jul-15 3:47
Dan Neely20-Jul-15 3:47 
GeneralRe: This company aims to launch rockets with beams of power Pin
enhzflep20-Jul-15 4:32
enhzflep20-Jul-15 4:32 
NewsIoT and Developers: Is reality meeting expectation? Pin
Kent Sharkey19-Jul-15 17:38
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NewsMandatory Windows 10 Home updates: The good, the bad, and the potentially ugly Pin
Kent Sharkey19-Jul-15 17:29
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GeneralRe: Mandatory Windows 10 Home updates: The good, the bad, and the potentially ugly Pin
Member 1168325119-Jul-15 21:13
Member 1168325119-Jul-15 21:13 
GeneralRe: Mandatory Windows 10 Home updates: The good, the bad, and the potentially ugly Pin
FIorian Schneidereit20-Jul-15 2:43
FIorian Schneidereit20-Jul-15 2:43 
GeneralRe: Mandatory Windows 10 Home updates: The good, the bad, and the potentially ugly Pin
Member 1168325120-Jul-15 3:45
Member 1168325120-Jul-15 3:45 
GeneralRe: Mandatory Windows 10 Home updates: The good, the bad, and the potentially ugly Pin
Dan Neely23-Jul-15 3:04
Dan Neely23-Jul-15 3:04 
GeneralRe: Mandatory Windows 10 Home updates: The good, the bad, and the potentially ugly Pin
Member 1168325124-Jul-15 3:23
Member 1168325124-Jul-15 3:23 
GeneralRe: Mandatory Windows 10 Home updates: The good, the bad, and the potentially ugly Pin
Dan Neely25-Jul-15 10:09
Dan Neely25-Jul-15 10:09 
NewsLatest Flash Player version has improved exploit defenses Pin
Kent Sharkey19-Jul-15 17:27
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GeneralRe: Latest Flash Player version has improved exploit defenses Pin
Patrice T20-Jul-15 5:54
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NewsFor the first time in 12 years, less than half of emails are spam Pin
Kent Sharkey19-Jul-15 17:25
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GeneralRe: For the first time in 12 years, less than half of emails are spam Pin
TheGreatAndPowerfulOz20-Jul-15 5:23
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NewsAll editions of Windows 10 get 10 years of updates, support Pin
Kent Sharkey19-Jul-15 17:23
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GeneralRe: All editions of Windows 10 get 10 years of updates, support Pin
irneb19-Jul-15 23:10
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GeneralRe: All editions of Windows 10 get 10 years of updates, support Pin
Kevin McFarlane20-Jul-15 0:09
Kevin McFarlane20-Jul-15 0:09 

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