為甚麼電流表串聯在電路上
回答 (5)
2009-04-23 1:24 am
The Resistance Of Ammeter Is Low,,
If The Ammeter Connect In Parallel,,
It May Cause Short Circuit,,
So If The Resistance Is Low,,
It Must Connect In Series To Make Sure That
It Can't Upset The Circuit But Still Can Measure The Current
If The Ammeter Connect In Parallel,,
It May Cause Short Circuit,,
So If The Resistance Is Low,,
It Must Connect In Series To Make Sure That
It Can't Upset The Circuit But Still Can Measure The Current
2009-04-22 8:08 pm
電流錶必須用串聯，是因為：
1) ammeter 是量度電路上使用的電流 -Amp，若果並聯便型成分流，並不是量度的電流數據。
2) 由於 ammeter 的內阻大低，並聯便好像型成一個短路，引致燒錶。
1) ammeter 是量度電路上使用的電流 -Amp，若果並聯便型成分流，並不是量度的電流數據。
2) 由於 ammeter 的內阻大低，並聯便好像型成一個短路，引致燒錶。
2009-04-22 7:46 pm
Simply speaking, ammeter is an instrument used to measure electric current, and electric current is a flow of charges.
Therefore, if you wish to measure the "flow of charges" at a point on an electric circuit, you must connet an instrument at that point in order to "catch this flow of charges". Obviously, the ammeter has to be inserted at that particular point to let charges flow through it. This is in fact a series conection.
Therefore, if you wish to measure the "flow of charges" at a point on an electric circuit, you must connet an instrument at that point in order to "catch this flow of charges". Obviously, the ammeter has to be inserted at that particular point to let charges flow through it. This is in fact a series conection.
2009-04-22 8:05 am
在直流的量度來說，電壓表和電流表的表頭係同一樣野，只視乎如何將它與附助電路配合，之後才能成為電壓表或電流表，其實最終對表頭來講都係量度電壓，電壓表用分壓電阻，而電流表就係量度串聯於電路中的電阻兩端的電壓差，從而顯示出電流狀況，故直流電流表必須串接於電路上才可工作。
至於量度交流電流，會利用磁場的強弱，通過磁感應（就如一個小型變壓器，初級是所測電器的一條回路，次級接至鉗表電路）及再整流後通過表頭顯示出來。
至於量度交流電流，會利用磁場的強弱，通過磁感應（就如一個小型變壓器，初級是所測電器的一條回路，次級接至鉗表電路）及再整流後通過表頭顯示出來。
2009-04-22 6:16 am
電流表要串聯在電路上既係直接電流表，其實仲有含分流器既電流表，含互感器電流表，鉗形電流表，叉形電流表等好多種。
2009-04-21 22:34:01 補充：
爲什麽？ 只有一個理由，要量電流量。
2009-04-21 22:34:01 補充：
爲什麽？ 只有一個理由，要量電流量。
收錄日期: 2021-04-25 19:27:32
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https://hk.answers.yahoo.com/question/index?qid=20090421000051KK01246