问题 选择题

将一小段通电直导线垂直于磁场方向放入某磁场中,导线会受到一定大小的安培力作用;若保持直导线长度和其中的电流不变,将它垂直于磁场方向放入另一较强的磁场中,发现导线所受的安培力会变大。下列说法中正确的是 (  )

A.磁场的磁感应强度由导线所受的安培力决定

B.磁场的磁感应强度随导线所受的安培力的增大而增大

C.磁场的磁感应强度由磁场本身决定

D.在任何情况下,通电导线所受安培力的大小都能反映磁场的强弱

答案

答案:C

题目分析:磁场的磁感应强度与外界因素无关,由磁场本身的性质决定,所以ABD均错。

点评:此类题型考察了磁场的性质,磁场的强弱与外界因素无关,由场自身决定。

判断题
单项选择题

A narrowing of your work interests is implied in almost any transition from a study environment to managerial or professional work. In the humanities and social sciences you will at best reuse only a fraction of the material (1) in three or four years’ study. In most career paths academic knowledge only (2) a background to much more applied decision-making. Even with a " training " form of degree, (3) a few of the procedures or methods (4) in your studies are likely to be continuously relevant in your work. Partly this (5) the greater specialization of most work tasks compared (6) studying. Many graduates are not (7) with the variety involved in (8) from degree study in at least four or five subjects a year to very standardized job (9) . Academic work values (10) inventiveness, originality, and the cultivation of self-realization and self-development. Emphasis is placed (11) generating new ideas and knowledge, assembling (12) information to make a " rational " decision, appreciating basic (13) and theories, and getting involved in fundamental controversies and debates. The humanistic values of higher (14) encourages the feeling of being (15) in a process with a self-developmental rhythm. (16) , even if your employers pursue enlightened personnel development (17) and invest heavily in " human capital " —for example, by rotating graduate trainees to (18) their work experiences—you are still likely to notice and feel (19) about some major restrictions of your (20) and activities compared with a study environment.

(1)()

A.restricted

B.covered

C.spread

D.confirmed