问题
不定项选择
如图所示,理想变压器原、副线圈匝数之比为20:1,原线圈接正弦交流电源,副线圈接入“220V,60W”灯泡一只,且灯泡正常发光。则

A.电流表的示数为A
B.电源输出功率为1200W
C.电流表的示数为A
D.原线圈端电压为11V
答案
答案:C
如图所示,理想变压器原、副线圈匝数之比为20:1,原线圈接正弦交流电源,副线圈接入“220V,60W”灯泡一只,且灯泡正常发光。则
A.电流表的示数为A
B.电源输出功率为1200W
C.电流表的示数为A
D.原线圈端电压为11V
答案:C
A legally binding promise to buy 140 oz. of gold two months from now at a price agreed upon today is a(n) :
A.
A. take-or-pay contract. |
B.
B. forward commitment. |
C.
C. option. |