閃電好似擊中橋墩？勁！

[anyone]

剛從家中拍到，閃電好似擊中橋墩？

[Tinping]

Wow!!!! Good shot!

[anyone]

橋墩上是否有避雷針的設備？

[Chanlunlun]

剛從家中拍到，閃電好似擊中橋墩？

Dear mr. One,

I can't belief that you tookt that picture at the right moment !

Yes, the lightning hit deadly right on top of the bridge. I saw it too, at a much closer distance.

Best regards
Chan Yuk Lun

[anyone]

剛從家中拍到，閃電好似擊中橋墩？

Dear mr. One,

I can't belief that you shot that picture at the right moment !

Yes, the lightning hit deadly right on top of the bridge. I saw it too, at a much closer distance.

Best regards
Chan Yuk Lun

wow , 那麼，橋墩上應該有避雷針的設備，否則就危險了！

[Chanlunlun]

Surely it has. Otherwise there will be an explosion.

[鄧登凳]

橋墩上是否有避雷針的設備？

橋墩一般都有避雷針, 而你的圖是橋墩上的避電針向空中放電--在源頭是單一電漿線, 到尾開叉。

[anyone]

再上多幾幅同大家分享。

[anyone]

橋墩上是否有避雷針的設備？

橋墩一般都有避雷針, 而你的圖是橋墩上的避電針向空中放電--在源頭是單一電漿線, 到尾開叉。

謝謝 tang sir 教導，愚蠢學生都係唔多明；遲些見面再討教。

[simonii]

橋墩上是否有避雷針的設備？

橋墩一般都有避雷針, 而你的圖是橋墩上的避電針向空中放電--在源頭是單一電漿線, 到尾開叉。

謝謝 tang sir 教導，愚蠢學生都係唔多明；遲些見面再討教。

意思是閃電的電其實是由地面物件向上放電, 而不是平日所說的, 從天上劈下來.

[bingsze]

橋墩上是否有避雷針的設備？

橋墩一般都有避雷針, 而你的圖是橋墩上的避電針向空中放電--在源頭是單一電漿線, 到尾開叉。

謝謝 tang sir 教導，愚蠢學生都係唔多明；遲些見面再討教。

意思是閃電的電其實是由地面物件向上放電, 而不是平日所說的, 從天上劈下來.

more confusing,,,

I know that the ionised charges will move up to the clouds and guide the intense charges from the clouds to hit the ground, but what what is the meaning of the lightning is started from the ground and hitting the clouds???

[Wah!!]

Discovery 閃電影片:
http://www.youtube.com/watch?v=lhS9Im5PE-s

慢鏡頭顯示閃電係由雲開始向下發展, 當雲端的閃電接近地面時, 地面亦會有一支或以上的閃電向上伸. 最後接通天地線時, 就會有強烈的放電情況.

雲底的電荷係負, 而地面感生出來的電荷係正的.
平常所說的電流係正流向負, 所以就會認為電流係由地面流向雲.
若看電子流動的方向, 則應該係由雲流向地面.

[鄧登凳]

There are many kinds of ligthning. In some cases, the direction of development is shown by the branching (fork shape structure).

Check this link:
http://www.youtube.com/watch?v=7Y4an99MBGk

[鄧登凳]

more confusing,,,

I know that the ionised charges will move up to the clouds and guide the intense charges from the clouds to hit the ground, but what what is the meaning of the lightning is started from the ground and hitting the clouds???

Most secondary school textbooks over-simplify lightning and thunders.

In general, ligthning occurs with a negatively charged cloud bottom section sending negative charge towards the positively charged ground (Type: Negative cloud to ground).

According to a PPT on atmospheric physics from the University of Missouri: http://solberg.snr.missouri.edu/People/ ... 0-10.2.ppt This type accounts for 90% of lightning and is often the only type described in secondary school textbooks.

However, 2% of lightning is negative ground to cloud type with a negatively charged ground sending negative charges towards some positively charged clouds.

For others who may not remember school physics: whether something is negatively or positively charged in a macroscopic scale depends only on potential difference, which is relative. By convention, the ground is always zero in potential.

[funoooo]

受教！