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為何磁羅盤裡的磁針要短要強呢?
Why does magnet in a compass should be short and strong?

(a): Increase sensitive

(b):decrease deviation

(c):keep horizontal level

??????







  • 2013-04-26 13:25:44 補充


    我也覺得以上皆是,偏偏是單選題阿-.-:





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為何磁羅盤裡的磁針要短要強呢?
Why should the magnet in a compass be short and strong?

應該是以下皆是. 
 
(a) Increase sensitivity. 如果magnet不夠強, it can go through demagnetization, 也就是失去磁性. 相反的, 強磁性provides sensitivity(敏感度). 

(b) Decrease deviation. 強磁性也比較不容易被local magnetic field(所在地的磁場)影響. 

(c) Keep horizontal level. 短短的磁針比較容易在慈羅盤內平衡, keeping it horizontal and parallel to a flat surface.







  • 2013-04-26 13:47:31 補充


    可能(a)吧 如果(b)指的是angle deviation那就沒有影響 (c)只要磁針做的好, 有辦法平衡, 長短應該無關緊要.







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