问题 不定项选择

如图所示,实线为一匀强电场的电场线,两个带电粒子q1、q2分别从A、C两点以垂直于电场线方向的初速度射入电场,仅受电场力作用,运动轨迹分别如图中的ABC、CDA所示。已知q1是带正电的粒子。则下列说法中正确的是    

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A.q2可能也带正电

B.A点的电势一定低于C点的电势

C.电场力对q1做正功,对q2做负功

D.q1、q2的电势能均减少

答案

答案:D

单项选择题 A3/A4型题
单项选择题

Culture is activity of thought, and receptiveness to beauty and human feeling. (1) of information have nothing to do with it. A merely well-informed man is the most useless (2) on God’s earth. What we should (3) at producing is men who (4) both culture and expert knowledge in some special direction. Their expert knowledge will give them the ground to start (5) , and their culture will lead them as (6) as philosophy and as high as (7) We have to remember that the valuable (8) development is self-development, and that it (9) takes place between the ages of sixteen and thirty. As to training, the most important part is given by mothers before the age of twelve.

In training a child to activity of thought, above all things we must (10) of what I will call "inert ideas"—— that is to say, ideas that are merely (11) into the mind without being (12) , or tested, or thrown into fresh combinations.

In the history of education, the most (13) phenomenon is that schools of learning, which at one epoch are alive with a craze for genius, in a (14) generation exhibit merely pedantry and routine. The reason is that they are overlade with inert ideas. Except at (15) intervals of intellectual motivation, education in the past has been radically (16) with inert ideas. That is the reason why (17) clever women, who have seen much of the world, are in middle life so much the most cultured part of the community. They have been saved from this horrible (18) of inert ideas. Every intellectual revolution which has ever stirred humanity (19) greatness has been a (20) protest against inert ideas.

20()

A.violent

B.passionate

C.exempt

D.idealistic