造成套印不准的纸病有哪些?()
A.切边不齐
B.折痕
C.裂口
D.斑点
参考答案:A, C
一电阻额定功率为0.01W,阻值不详,用欧姆表粗测其阻值约为40kΩ,现有下列仪表元件,试设计适当的电路,选择合适的元件,较精确地没定其阻值.
①电流表,量程0-300μA,内阻150Ω;
②电流表:量程0-1500μA,内阻45Ω;
③电压表:量程0-3V,内阻6kΩ;
④电压表,量程0-15V,内阻30kΩ;
⑤电压表,量程0-50V,内阻100kΩ;
⑥直流电源,输出电压24V,额定电流0.5A
⑦滑动变阻器,0-50Ω,3W;
⑧滑动变阻器,0-2kΩ,1W;
⑨电键一只,连接导线足量
(1)电流表选______,电压表选______,滑动变阻器选______,(均填用电器前面的数字序号)
(2)在方框内画出电路图.
_____I remember most about my grandmother is that she showed her love through food
A.How
B.What
C.If
D.Whether