如图所示,平行金属板电容器上极板原带有负电,下极板接地,有一带电微粒悬浮在极板间

题型:填空题

问题:

如图所示,平行金属板电容器上极板原带有负电,下极板接地,有一带电微粒悬浮在极板间.己知绿光刚好能使该金属发生光电效应.现让红光、紫光分别照射在上级板上.则下列说法正确的是

 

A.红光照射过程中,带电粒子不发生运动,极板问不产生磁场

B.红光照射过程中,带电粒字向下运动,极板间产生磁场

C.紫光照射过程中,带电粒子不发生运动,极板间不产生磁场

D.紫光照射过程中,带电粒子向下运动,极板问产生磁场

考点:光电效应方程
题型:填空题

关节脱位后固定的益处有()

A.减少出血

B.有利组织修复

C.防止再脱位

D.防止骨化性肌炎

E.避免出现感染

题型:填空题

番泻叶所含的化学成分是()

A.蒽醌类

B.挥发油

C.生物碱

D.靛蓝及靛玉红

E.皂苷

题型:填空题

Since we are social beings, the quality of our lives depends in large measure on our interpersonal relationships. One strength of the human condition is our tendency to give and receive support from one another under stressful circumstances. Social support consists of the exchange of resources among people based on their interpersonal ties.

Those of us with p support systems appear better able to cope with major life changes and daily hassles (困难). People with p social ties live longer and have better health than those without such ties. Studies over a range of illnesses, from depression to heart disease, reveal that the presence of social support helps people fend off (挡开) illness, and the absence of such support makes poor health more likely.

Social support cushions stress in a number of ways. First, friends, relatives, and co-workers may let us know that they value us. Our self-respect is strengthened when we feel accepted by others despite our faults and difficulties. Second, other people often provide us with informational support. They help us to define and understand our problems and find solutions to them. Third, we typically find social companionship supportive. Engaging in leisure-time activities with others helps us to meet our social needs while at the same time distracting (转移……注意力) us from our worries and troubles. Finally, other people may give us instrumental support—financial aid, material resources, and needed services—that reduces stress by helping us resolve and cope with our problems.

Which of the following is closest in meaning to the word "cushions" (Line 1, Para. 2)().

A. Adds up to.

B. Does away with.

C. Lessens the effect of.

D. Lays the foundation for.

题型:填空题

以下哪一项对企业来说是间接变动成本()。

A.生产工人工资

B.生产用材料成本

C.销售佣金

D.财产税

题型:填空题

在Windows的窗口中,选中末尾带有省略号“…”的菜单意味着 (5) 。在下拉式菜单中,每条命令后都有一个用括号括起来的带下划线的字符,称为热键或快捷键,意味着 (6)

A.在显示出了下拉式菜单后,可以在键盘上按字符来选择命令

B.在任何时候可以直接在键盘上按字符来选择命令

C.在显示出了下拉式菜单后,可以按Alt+字符来选择命令

D.在任何时候可按Alt+字符来选择命令

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