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魯科學家導讀:

※ 引述《okura (大倉)》之銘言：
: 1.媒體來源:
: 英國dailymail
: 2.完整新聞標題:
: Is deep space travel a step closer to reality? Nasa reveals successful test
: of 'impossible' fuel-free engine that breaks the laws of physics
: 3.完整新聞內文:
: 摘要:
: EM Drive Fuel-free engine could take a spacecraft to Mars in 10 weeks.
: Creates thrust by bouncing microwaves in chamber, using solar power.
: Nasa has conducted more tests using an improved experimental process.
: Test designed to remove errors from earlier study but still produced thrust.
: Scientists still aren't sure how this happens as it defies the laws of physics.
: 全文:
: An 'impossible' fuel-free engine, which could take a humans to Mars in just
: 10 weeks, is still defying science after another batch of tests by Nasa
: suggested the thruster does work.
: The so-called EM Drive creates thrust by bouncing microwaves around in an
: enclosed chamber, and uses only solar power.
: When the concept was first proposed, it was considered implausible because it
: went against the laws of physics - and subsequent tests of the engine have
: shown that the idea could revolutionise space travel.
: March posted on the Nasa Spaceflight forum in reply to an unpublished paper
: that claims the unaccounted thrust is generated by something known as the
: Lorentz force.
EM Drive原理宣稱是利用勞倫茲力產生產生衝力
: The Lorentz force is the force that is exerted by a magnetic field on a
: moving electric charge.
勞倫茲力是磁場作用在移動電荷上的磁力
各位修過普通物理, 應該知道移動電荷在磁場受力
_    _   _         _      _
F=q (v x B) = q [(ds/dt) xB ]

但是要讓太空船加速, 此磁力必須作功來產生動能
   _ _      _   _   _        _      _    _
W= F.s = q (v x B). s = q [(ds/dt) xB ]. s = 0

而磁力跟位移的外積, 再跟位移取內積必為零
所以磁力必不做功!!
這則新聞裡提到動力來源是羅倫茲力, 肯定是錯的

看到這邊, 已經可以知道這則新聞必定是唬爛
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詳細的網頁介紹

NASA 證實"不可能"的太功船嗎? 一句話, 不
Did NASA Validate an “Impossible” Space Drive? In a Word, No.
http://goo.gl/EW8V2I

壞科學, 壞科學記者: EM Drive
Bad science, bad science journalism: the EmDrive
http://nanoscale.blogspot.com/2015/04/bad-science-bad-science-journalism.html

沒有跳躍引擎: NASA對EM Drive不予重視
No Warp Drive Here: NASA Downplays 'Impossible' EM Drive Space Engine
http://goo.gl/JAu35l


節錄一段NASA的測試:
It's tens of micronewtons, less than the weight of a snowflake," Siegel told
Space.com. Specifically, Siegel said he is seeing reports of anywhere between
50 and 70 micronewtons. The error bar of measurement, however, is reported as
between 15 and 30 micronewtons.

NASA測試EM drive, 結果得到 數十微牛頓的衝力
大約跟一片雪花的重量差不多
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給end的你,
歹年冬, 猴肖人
EM drive 是糟糕科學家跟不專業的記者一起搞出來的笑話




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