現(xiàn)要測定一只額定電壓是3.8V的小燈泡的額定功率,己經(jīng)知道小燈泡的額定功率小于2W,電路圖如圖甲所示,所用的元件如圖乙所示.
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![](http://thumb.zyjl.cn/pic6/res/czwl/web/STSource/20131024150344135042368/SYS201310241503441350423024_ST/images1.png)
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(1)根椐圖甲的電路圖,用筆劃線代替導(dǎo)線將圖乙的實(shí)驗(yàn)器材連成電路,注意連線不要交叉.
(2)電路閉合前,滑動(dòng)變阻器的滑片應(yīng)調(diào)到阻值______的位置.
(3)電路閉合后,調(diào)節(jié)滑動(dòng)變阻器使電壓表的示數(shù)為______V,這時(shí)電流表的示數(shù)如圖丙所示,電流表的讀數(shù)為______,小燈泡的額定功率為______.