S*********4 发帖数: 5125 | 1 National Ignition Facility achieves unprecedented 1 megajoule laser shot
The National Nuclear Security Administration (NNSA) announced today that
scientists at the National Ignition Facility (NIF) at Lawrence Livermore
National Laboratory (LLNL) have successfully delivered an historic level of
laser energy — more than 1 megajoule — to a target in a few billionths of
a second and demonstrated the target drive conditions required to achieve
fusion ignition.
This is about 30 times the energy ever d |
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x******g 发帖数: 33885 | 2 炮弹飞行速度为每小时5000英里。每分钟十发,打100英里外的目标。
http://news.yahoo.com/navy-railgun-tests-leading-ship-superweap
The first weapon-scale prototype of a futuristic Navy railgun began
undergoing firing tests last week, the next big step toward putting the
electromagnetic superweapon on U.S. warships by 2020. The Navy envisions
using railguns to destroy enemy ships, defend against enemy missiles, or
bombard land targets in support of Marines hitting the beaches.
Newly released video shows the prototype railgun us... 阅读全帖 |
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发帖数: 1 | 3 估计投入100 megajoules,收获0.1 megajoules
又赢了 |
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发帖数: 1 | 4 That's a 35 kg projectile, which leaves the muzzle with 115 megajoules and
arrives with 50 megajoules. I expect it'll punch through about 2 kg/cm^2 of
material when it arrives, which is about 8 meters of concrete.
https://www.quora.com/How-does-the-US-Navy-rail-gun-work-That-must-need-an-
insane-instantaneous-current-How-do-they-get-that-How-do-they-keep-it-from-
melting
貌似能量不少。
但是好像只对hard target有用。
For example, a rail gun projectile hitting a hard target like a tank or
concrete bunker will und... 阅读全帖 |
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p*********e 发帖数: 32207 | 7 奇怪的是"
The bullet would take just minutes to fire over 100 miles and would hit with
pinpoint accuracy with a velocity that's impossible in conventional guns
.
"
用的是"would take跟would hit",而不是took跟hit
与此相对的,
"A shot fired by the electromagnetic railgun at the Naval Surface Warfare
Centre in Dahlgren, Virginia, generated 33 megajoules of force out of the
barrel, a world record for muzzle energy and more than three times the
previous
record.
"
这里用的是"generated"
所以我猜测,前面一句只是将来的预期,而后面一句是实际的实验结果.
Read mo... 阅读全帖 |
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o*****s 发帖数: 1445 | 9 In June 2006, Tesla Motors reported the Roadster's battery-to-wheel
efficiency as 110 W·h/km (17.7 kW·h/100 mi) on an unspecified driving
cycle—either a constant 60 mph (97 km/h)) or SAE J1634 test—and stated a
charging efficiency of 86% for an overall plug-to-wheel efficiency of 128 W
·h/km (20.5 kW·h/100 mi).[37][122][123]
Evolution of the Roadster's plug-to-wheel efficiency (smaller values
indicate better efficiency)In March 2007, Tesla Motors reported the Roadster
's efficiency on the EPA hi... 阅读全帖 |
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c*********r 发帖数: 19468 | 10 也可能吧,R&T原文有点不清楚:
Some of the numbers being mentioned as possible combined horsepower and KERS
power took the concept to the outer edges of reason. Marshall explained the
early targets were in the 2000-hp range with the use of an 8-megajoule "
double" Flybrid system fitted to the car, but practical limitations lowered
the bar to approximately 1500 hp. |
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