(1)一物体与轻质弹簧相连静放在足够长的光滑斜面上,若外力将物体拉离平衡位置,撤

题型:问答题

问题:

(1)一物体与轻质弹簧相连静放在足够长的光滑斜面上,若外力将物体拉离平衡位置,撤去外力后物体开始运动,不计空气阻力,论证物体的运动是否是简谐运动(写出论证过程才能得分)

(2)一列横波上有相距4m的A、B两点,波的传播方向是由A向B,波长大于2m,如图所示的是A、B两质点的振动图象,求:这列波的波v.

考点:波长、频率和波速横波与纵波
题型:问答题

腹股沟疝修补术,切口感染化脓,下列哪项描述正确()。

A.Ⅰ-甲

B.Ⅰ-乙

C.Ⅰ-丙

D.Ⅱ-甲

E.Ⅱ-丙

题型:问答题

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.

题型:问答题

冷库设置防潮隔汽层的目的是()。

题型:问答题

某同学准备设计制作一个受光控又可以远程遥控的台灯,为了完成这个项目他学习了电子感应知识、电路知识、无线电知识等有关知识。这说明了技术的()

A.专利性

B.创新性

C.综合性

D.两面性

题型:问答题

片剂加入的黏合剂是

A.可压性淀粉
B.羧甲基纤维素钠
C.微粉硅胶
D.羧甲基淀粉钠
E.交联聚维酮水溶液

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