一段电路两端的电压为U,通过该段电路的电流为I,则该段电路的电功率P等于()。A.P

题型:单项选择题

问题:

一段电路两端的电压为U,通过该段电路的电流为I,则该段电路的电功率P等于()。

A.P=UI

B.P=UI2

C.P=U/I

考点:电工进网证考试电工进网证(低压类)电工进网证(低压类)题库
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凡是兄弟就用线连起来,然后去掉双亲到子女的连线,只留下双亲到第一个子女的连线不去掉,这种方法是

A.树转为树林的方法

B.把二叉树转为树和树林的方法

C.把树和树林转为二叉树的方法

D.把树林转为树的方法

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Popeye the Sailor first became a popular cartoon in the 1930s. the sailor in that cartoon ate lots of spinach to make him strong. People watched him, and they began to buy and eat a lot more spinach. Popeye helped sell 33 percent more spinach than before! Spinach became a necessary part of many people’s diets. Even some children who hated the taste began to eat the vegetable.

Many people thought that the iron in spinach made Popeye strong, but this is not true. Spinach does not have any more iron than any other green vegetable.

People only thought spinach had a lot of iron because the people who studied the food made a mistake. In the 1890s, a group of people studied what was inside vegetables. This group said that spinach had ten times more iron than it did. The group wrote the number wrong, and everyone accepted it.

Today, we know that the little iron in spinach cannot make a difference in how strong a person is. However, spinach does have something else which the body needs—folic acid.

It is interesting to point out that folic acid can help make a person strong. Maybe it was really the folic acid that made Popeye strong all along.

小题1:A good title for this reading passage is______.

A.Popeye the Sailor

B.The Truth About Spinach

C.A Mistake with Numbers

D.Folic Acid Makes You Strong小题2:Why did many people eat spinach after they saw Popeye the Sailor?

A.People liked folic acid.

B.They thought Popeye was funny.

C.Spinach had a lot of iron.

D.They thought spinach made them strong.小题3:A research group told people that spinach______.

A.made Popeye strong

B.was a green vegetable

C.had less iron than other green vegetables

D.had more iron than other green vegetables小题4:The reading passage says that perhaps Popeye got his strength from______.

A.iron

B.spinach

C.folic acid

D.exercise

题型:单项选择题

主治疥癣湿疹,虚寒冷哮,应选用的药物是()

A.雄黄

B.芡实

C.乌梅

D.硫黄

E.白矾

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9190_T00本地MIC送话无声问题,与以下哪个器件关联性最大?()

A.U1600(音频处理器)

B.U1302(射频开关)

C.U7100(RF收发器)

D.U1801(背光驱动芯片)

题型:单项选择题

3/2断路器接线有何优、缺点?

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