![](https://i.imgur.com/uvvTOaw.jpg)
[問題] 平均功率問題消失
![](https://i.imgur.com/uvvTOaw.jpg)
94題
不好意思想請問
平均功率不是應該是=Vrms^2/RL嗎
但是參考書上怎麼是用平均值電壓去算
參考書是不是寫錯了..
附解析
http://i.imgur.com/z4iiWjX.jpg
![](https://i.imgur.com/z4iiWjX.jpg)
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10/09 04:01, , 1F
10/09 04:01, 1F
可是書上都寫用有效值
※ 編輯: decfrvgtbhyn (1.170.192.186), 10/09/2016 04:04:34
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我上面寫錯了 應該是
110√2/10=11√2 (變壓器降壓)
11√2/2=5.5√2 (半波有效值)
(5.5√2)^2/1k (Vrms^2/RL)
=60.5m
但題目沒這選項?!
※ 編輯: decfrvgtbhyn (1.170.192.186), 10/09/2016 16:42:35
※ 編輯: decfrvgtbhyn (1.170.192.186), 10/09/2016 16:43:03
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