试题与答案

如图所示为一磁流体发电机示意图,A、B是平行正对的金属板,等离子体(电离的气体,

题型:选择题

题目:

如图所示为一磁流体发电机示意图,A、B是平行正对的金属板,等离子体(电离的气体,由自由电子和阳离子构成,整体呈电中性)从左侧进入,在t时间内有n个自由电子落在B板上,则关于R中的电流大小及方向判断正确的是(  )

A.I= ,从上向下

B.I= ,从上向下

C.I= ,从下向上

D.I= ,从下向上

答案:

答案:A

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题型:单项选择题

下列有关补贴的说法不正确的是 ( )

A.补贴,是指能为接受者带来利益的财政资助以及任何形式的收入和价格支持,这种资助或支持的提供者不仅包括一国政府还包括该国的公共机构

B.《反补贴条例》所针对的补贴不仅包括专向补贴,还包括普遍性补贴

C.以出口实绩为条件的补贴被视为专向补贴

D.在确定补贴的专向性时,还应当考虑受补贴企业的数量和企业受补贴的数额、比例、时间以及给与补贴的方式等因素

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