实验证明，磁力线、电流、导体受力，这三者的方向（）时，公式F_爱下问搜题

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问题单项选择题

实验证明，磁力线、电流、导体受力，这三者的方向（）时，公式F＝B.LI成立。

A.一致

B.互相垂直

C.相反

D.不一致

答案

参考答案：B

单项选择题

冷库的库址选择要合理、科学，减少经营管理费用和加快建设速度。以下（）情况不适合建设冷库。

A、靠近江河或深井

B、交通运输便利

C、靠近化工厂

D、工业区的上风地带

填空题

Tidiness

Tidiness means keeping things out of sight and yet available when wanted. It implies that there is a (1) for everything and that each thing used finds its way (2) to its place by a continuos process, not by a spasmodic (3) . The process depends, however, upon the drawer, cupboard and storage (4) being provided, for lack of which one things may literally have (5) place to go. Like the perambulator and trolley, the luggage and the golfclubs (6) be homeless. The same may be true of the deck-chairs (7) the bulkier plastic toys. As there is no place for them, it is no (8) telling people to put them away. The architect who thus economises on (9) space is apt to claim that a good-sized sitting-room is (10) result. What advantage is there in that, however, (11) half the living-room has to be used for storage The aesthetic (12) depends, in turn, upon storage space. (13) it may be true that no house ever had cupboards enough, (14) are some houses which have practically no cupboards (15) all. In these our choice must lie between chronic (16) and ruthless destruction. That is not to say, however, (17) cupboard space will itself create tidiness. Some people (18) happier, it would seem, in chaos. There is the question, furthermore, (19) the cupboards themselves are tidy. That (20) has been swept out of sight is no proof, in itself, that everything can be found.