[問題] 小鳥站在電線上不會觸電?
大家好
想請問幾個問題
1. 小鳥為何兩隻腳站在高壓電線上不會觸電?
我看網路上的說明都不太一樣,其中
http://www.phy.ntnu.edu.tw/demolab/phpBB/index.php/viewtopic.php?topic=16087
是說兩腳電位差=0
但我無法理解這句話的意思
我自己的解釋法是,電線電阻小於小鳥身體電阻,所以電流流經電線,不流身體
或是微量流經身體
兩腳電位差=0,不就是說兩腳間沒有電阻?
但我覺得電線還是身體都會有電阻阿,只是一個電阻很大,一個很小
所以電流選擇性流經某一條路線
不知道我的想法對不對?
2. 單一凸透鏡成像,如果物體原先在一倍焦距到二倍焦距間,現在把凸透鏡的
周圍塗黑,只剩下中間部分可以透光,那麼像會發生什麼事?
我認為像的位置和大小長度都不辨,因為那是跟物距和焦距有關
塗黑凸透鏡不會改變焦距,但是會造成像的顏色較暗
不知道我的想法對不對?
謝謝大家
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◆ From: 115.43.154.231
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如果說小鳥那兩腳間的電位差=0
不也就代表那小段電線的電位差=0?
那這樣高壓電傳輸就永遠不會在電線上消耗能量
畢竟沒有電位差-->P=0
這樣好像怪怪的??
※ 編輯: Ertkkpoo 來自: 115.43.154.231 (02/22 01:16)
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但我看到參考書中答案是給 電位差=0
所以不知道我的解釋方法(類似電阻並聯,鳥體電阻相對大)這樣的講法是否較好?
因感覺電位差=0是近似結果
謝謝大家
※ 編輯: Ertkkpoo 來自: 115.43.154.231 (02/22 01:29)
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不好意思,剛又突然想到,電線不都有包絕緣材料在銅線外?
那這樣不管鳥怎麼站,不都不會被電嗎? 還是說他的電線和一般電線不同? 謝謝大家
※ 編輯: Ertkkpoo 來自: 115.43.154.231 (02/22 01:35)
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