基于MATLAB的椭圆摆简谐振动周期的数值计算

用Matlab研究了椭圆摆的角加速度θ^..与θ摆角的关系,发现在很多情况下它们很接近线性关系,椭圆摆作很近似的简谐振动,研究了振动的周期随物块与质点的质量比m2／m1、圆弧线的半径r、质点刚开始运动时的摆角岛的变化关系．发现当质点刚开始运动时的摆角岛比较大时,椭圆摆还能作很近似的简谐振动,且振动的周期随如的增大而增大．     

几个值得注意的振动问题

1 作简谐振动的单摆的平衡位置 关于作简谐振动的单摆的平衡位置,有一种意见认为:“单摆的摆球通过最低点时,在竖直方向上的作用力并不平衡,故最低点不能叫做平衡位置,只能叫做最低位置。”为了弄清这个问题,必须强调:(1)单摆作为振动的例子,是指摆球沿圆弧的往复运动,它的向心力只改变摆球的运动方向,而不改变摆球在弧线上运动的快慢。因此,在研究摆球运动的回复力时,不必考虑向心力,只需考虑重力沿圆弧切线方向的分力。而摆球在最低位置时这一切向分力为零,所以从摆动的方面讲这一位置是平衡位置。(2)只有当摆角很小(不超过5°时,单摆的回复力才近似满足F=-k(?)的条件。所以只有当摆角很小时,单摆的运动才可当作简谐振动,而当摆角很小时,圆弧也可近似看成直线了。     

三线摆扭转运动视为简谐振动的条件

采用理论分析和数值计算,分析了将三线摆小角扭转视为简谐振动带来的振动周期偏差.结果表明,周期偏差随上圆盘半径与两盘高度之比及扭转角振幅的增加而增大.使用长摆线结构的三线摆,并使角振幅不大于5°时,用简谐振动近似得到的周期公式计算刚体转动惯量导致的误差将低于1/10 000.     

计算机辅助复摆实验

通过对复摆在非简谐振动情况下运动学方程的讨论,得到了复摆角速度同摆动次数的关系,并介绍了利用计算机进行辅助数据采集和处理的方法.     

单摆振动周期公式研讨

在重力场中的单摆,当摆角不大时(θ<5°),做简谐振动。摆线振动中心平衡位置为重垂线方向,振动周期T=2π(1/g)~(1/2),其中1为摆长,g为重力加速度。g值也可用单摆在平衡位置静止时,摆线张力F_o与摆球质量m之比来确定即:g=F_o/m,称为视重加速度。若使单摆处在非惯性系中,或使单摆处在电磁场中(摆球带电荷),或使单摆浸没在液体中,其振动是否仍是简谐振动?如是简谐振动,振动周期又怎样确定?笔者就以上问题分     

摆钟快慢问题的一种通用解法

我们知道,单摆作简谐振动时,摆的周期跟摆长的平方根成正比,跟重力加速度的平方根成反比,而且跟摆的质量、摆角的大小无关即.正因为T只与g、l有关,伽利略发现了单摆振动的等时性,后来惠更斯制成了摆钟用以计时.也就出现了摆钟快慢及其调整的问题. 摆钟快慢问题实际上讨论的是单摆周期T     

振动方程求解方法探究

本文介绍了研究振动方程时的几种分析方法,并讨论了方程解的物理意义。自然界中最基本的振动是简谐振动,讨论简谐振动是研究复杂振动现象的基础,对其研究和分析方法很多,本文介绍几种求解振动方程的几种分析方法：1.常系数线性微分方程的一般求解法;2.拉普拉斯逆变换法;3.简谐振动的矩阵求解法,并讨论了方程解的物理意义。     

三法解决复摆小振动周期问题

对高中物理竞赛中复摆做小角度振动的周期问题作了讨论,将质点振动与刚体振动类比,得出复摆小角度振动的周期公式;将复摆与单摆类比,利用折合摆长法和角速度类比法对复摆小振动的周期进行求解。     

应用探索式教学法的几则实例

１．问题讨论式教学问题讨论式教学的基本框架是：创建情境，发现并提出问题→个体或小组活动，猜想，假设→探索讨论，论证，形成结论→归纳总结，完善结论在这里问题是线索，学生主体性活动贯穿于教学全过程，思维活动沿着生疑设疑释疑解疑过程进行。“归纳总结，完善结论”是认识的升华过程，也是创新的过程。例如在《单摆》一节的教学中，在讨论完什么是单摆、在什么情况下单摆的振动是简谐振动后，在研究单摆的振动周期与哪些因素有关时，可鼓励学生大胆推测。学生推测的结果是：单摆的振动周期①跟摆球的质量有关；②跟摆角（振…     

判定简谐振动的一种简便方法

本文给出一种判定一个振动是否为简谐振动的简便方法——能量守恒法：它是通过列写任意时刻 ｔ 振动系统的能量守恒方程,然后同时对时间 ｔ 求导,给出任意时刻 ｔ 振动物体的加速度与位移之间的关系,从而判定振动是否为简谐振动．它比起传统方法具有快速、方便、准确之优点     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…