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问题 填空题

某导体两端的电压为12伏，通过它的电流为0.6安，10秒内通过该导体横截面的电荷量为 _______ 库，其电阻为        欧。当通过它的电流为0.3安时，该导体的电阻为       欧。

答案

6  20  20  

题目分析：电流是由电荷的定向移动形成的，在单位时间内通过导体的电荷量越多，电流就越大，根据公式可得，Q=It=0.6A×10s=6C。电阻的大小可以利用欧姆定律进行计算，根据得。电阻是导体的一种属性，它的大小与导体的材料、长度、横截面积有关，与导体两端的电压和电流大小无关。欧姆定律只是用于计算电阻的大小，

单项选择题 A1/A2型题

体温调节中枢功能失常导致的发热，常见于（）

A.中暑

B.安眠药中毒

C.颅骨骨折

D.脑震荡

E.甲状腺功能亢进
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填空题

Motivation is "the driving force within individuals that impels them to action." And goals are the sought-after results_____(1) motivated behavior.Motivation can be either positive or negative_____(2) direction. We may feel a driving force toward some object or condition, _____(3) a driving force away from some object or condition. For example, a person may be impelled toward a restaurant to fulfill a need, hunger, and away_____(4) an airplane to fulfill a need of safety. Some psychologists refer to positive drives_____(5) needs, wants or desires,_____(6) negative drives as fears or aversions._____ (7), though negative and positive motivational forces seem to differ dramatically_____(8) terms of physical and sometimes emotional activity, they are basically similar in_____(9) they both serve to initiate and sustain human behavior.____(10) this reason, researchers often refer _____(11) both kinds of drives or motives as needs, wants and desires.Goals, _____(12), can be either positive or negative. A positive goal is one toward_____ (13) behavior is directed and it is often referred to as an approach object. A negative goal is _____(14) from which behavior is directed away and it is sometimes referred to as an avoidance object. Since both approach and avoidance goals can be considered objectives of motivated behavior, most researchers refer to_____(15) types simply as goals. Consider this example. A middle-aged woman may wish to remain_____(16) attractive as possible. Her positive goal is to appear desirable, and_____(17) she may use a perfume advertised to make her irresistible. A negative goal may be to prevent her skin_____(18) aging, and therefore she may buy and use face creams._____(19) the former case, she uses perfume to help her achieve her positive goal — attractiveness; in the____(20) case, she uses face creams to help avoid a negative goal — wrinkled skin.
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