“运动和力”例题选析和对应训练

例1著名短跑运动员卡·刘易斯曾经以9．86s跑完100m。在这次赛跑中，从起跑点算起每10m所用时间分别是：1．88s，1．08s，0．92s，0．89s，0．84s，0．84s，0．84s，0．83s，最后20m用了1．74s。从这给数据可以算出，他跑完100m的平均速度是——m／s，平均速度最小的是第——个10m，平均速度最大的是第——个10m。(第七届全国初中应用物理知识竞赛试题)

吹响“运动和力”的集结号

“运动和力”介绍了运动学的基础知识、牛顿第一定律及其相关的内容，主要是一些基本概念、运动规律和研究方法。力学的概念、规律，特别是其研究方法和物理思想，对其他运动形式的研究具有重要的意义。另外，这部分知识应密切联系生活、生产和社会实际，对科学探究过程的某些具体步骤，尤其是对实验数据的处理，要经历基本的科学探究过程，学会用探究结果进行分析、论证。下面结合2008年中考试题解读“运动和力”的重要考点及解题方法。

从源于生活的问题中引导学生提出科学假说——以小学科学“运动和力”的教学为例

在义务教育课程标准实验教科书《科学》赢年级上册中，有一部分是以介绍物理学中运动和力为内容的，其中有一个实验场景“我们的小缆车”，这个实验的设计是将一个玩具小车放在水平的桌面上，一端拴上细绳，细绳的另一端拴在铁钩上挂在桌角，不断增加垫圈的个数，

人教版《义务教育课程标准实验教科书·物理(九年级)》第十一章“运动和力”教材分析

本章内容共有三大部分:运动、力、运动和力的关系。这些内容非常贴近学生生活,却又和学生的生活经验矛盾重重,特别是力和运动的关系这部分内容,是力学所要解决的中心课题,也是物理学的基础,对学生掌握知识、提高能力,形成科学批判能力是非常重要的。本文从教材特色和教学建议两个方面对本章内容做如下阐述。

“运动和力”典型问题分析

例1如图1所示,质量为2 kg的石块用细绳悬挂后静止在半空中,分析石块受到哪些力的作用?各力的大小、方向如何?

“运动和力”考点例析

考点一、运动的描述 例1 如图1所示，小华和小星两人站在地面上，小纬乘坐在沿水平方向匀速飞行的飞机上，某时刻自由释放了一个玩具，若不考虑空气阻力。其中小纬观察到物体垂直下落的现象是以（）。

“运动的描述”教学设计及反思

（本课选自人教版义务教育课程标准实验教科书《物理》九年级第十二章“运动和力”第一节。） 教材分析： 这是学生认识机械运动的开始，也是力学的基础知识。机械运动的引出，科学地描述了人们对运动的认识，体现了科学的严密性和完整性。教材从生活实际引导学生学习物理知识，真正体现了“从生活走向物理，从物理走向社会”这一新的课程理念，

Effects of core and non-dominant arm strength training on drive distance in elite golfers

Background： Various training schemes have sought to improve golf-related athletic ability. In the golf swing motion, the muscle strengths of the core and arms play important roles, where a difference typically exists in the power of arm muscles between the dominant and non- dominant sides. The purposes of this study were to determine the effects of exercises strengthening the core and non-dominant arm muscles of elite golf players （handicap 〈 3） on the increase in drive distance, and to present a corresponding training scheme aimed at improving golf performance ability. Methods： Sixty elite golfers were randomized into the control group （CG, n = 20）, core exercise group （CEG, n = 20）, and group receiving a combination of muscle strengthening exercises of the non-dominant arm and the core （NCEG, n = 20）. The 3 groups conducted the corresponding exercises for 8 weeks, after which the changes in drive distances and isokinetic strength were measured. Results： Significant differences in the overall improvement of drive distance were observed among the groups （p 〈 0.001）. Enhancement of the drive distance of NCEG was greater than both CG （p 〈 0.001） and CEG （p = 0.001）. Except for trunk flexion, all variables of the measurements of isokinetic strength for NCEG also showed the highest values compared to the other groups. Examination of the correlation between drive distance and isokinetic strength revealed significant correlations of all variables except trunk flexion, wrist extension, and elbow extension. Conclusion： The combination of core and non-dominant arm strength exercises can provide a more effective specialized training program than core alone training for golfers to increase their drive distances.

Prediction of Aircraft＇s Longitudinal Motion Based on Aerodynamic Coefficients and Derivatives by Surrogate Model Approach

The accuracy of a flight simulation is highly dependent on the quality of the aerodynamic database and prediction accuracies of the aerodynamic coefficients and derivatives. A surrogate model is an approximation method that is used to predict unknown functions based on the sampling data obtained by the design of experiments. This model can also be used to predict aerodynamic coefficients/derivatives using several measured points. The objective of this paper is to develop an efficient digital flight simulation by solving the equation of motion to predict the aerodynamics data using a surrogate model. Accordingly, there is a need to construct and investigate aerodynamic databases and compare the accuracy of the surrogate model with the exact solution, and hence solve the equation of motion for the flight simulation analysis. In this study, sample datas for models are acquired from the USAF Stability and Control DATCOM, and a database is constructed for two input variables （the angle of attack and Mach number）, along with two derivatives of the X-force axis and three derivatives for the Z-force axis and pitching moment. Furthermore, a comparison of the value predicted by the Kriging model and the exact solution shows that its flight analysis prediction ability makes it possible to use the surrogate model in future analyses.

解读牛顿运动定律

牛顿运动定律是高中物理的重点和难点．牛顿三定律集中解释了一个问题，那就是“运动和力”的关系问题，那么定律是怎样层层揭示这个关系，阐述这个规律的呢？下面本人就各个定律进行解读．

Effect of moxibustion at Shénquè(神阙 CV 8) on anti-exercise-induced fatigue in exhaustive rats in varying degrees

Objective To explore the effect of moxibustion at Shenque （神阙 CV 8） on the anti-exercise-induced fatigue in rats after exhaustive exercise in varying degrees. Methods Seventy-two SD rats were randomly divided into 3 groups according to the random number table method, including blank group, model group and moxibustion group. The model group and moxibustion group were divided into 4 subgroups respectively, that was 1 time, 4 times, 7 times and 10 times subgroup. There were 9 groups with 8 rats in each group. Except blank group, all the rats were established into exhaustive models through swimming. Mild moxibustion at CV 8 was carried out for 15 min in the rats in moxibustion group after modeling for once every other day. The concentration of serum glucose （GLU）, malonaldehyde （MDA） and blood urea nitrogen （BUN） as well as the activity of aspartate transaminase （AST）, alanine transaminase （ALT） and lactic dehydrogenase （LDH） were detected 24h after the exhaustive exercise by adopting full-automatic analyzer. Results The exhaustive time of rats were long at first but shorter later. The exhaustive time of rats in the model group （4 times） were obviously longer than that in the model group （1 time） （P〈0.01）, the exhaustive time of rats in the model group （7 times） and model group （10 times） were obviously shorter than that in the model group （1 time） （P〈0.01）, and the exhaustive time of rats in the moxibustion group （7 times） and moxibustion group （10 times） were obviously longer than that in the model group with the same number of times （P〈0.01）, the serum GLU level of rats in the model group （7 times） and model group （10 times） increased when compared with the blank group （P〈0.01）, and the serum MDA and BNU levels as well as the activity of AST, ALT and LDH of rats in the model group （4 times）, model group （7 times） and model group （10 times） increased when compared with the blank group （P〈0.05 or P〈0.01）, the serum GLU, MDA and BNU levels as well as the activity of AST and ALT of rats in the moxibustion group （7 times） and moxibustion group （10 times） reduced when compared with the model group with the same number of times （P〈0.05 or P〈0.01）, and the serum LDH activity of rats in the moxibustion group （4 times）, moxibustion group （7 times） and moxibustion group （10 times） reduced when compared with the model group with the same number of times （P〈0.05 or P〈0.01）. Conclusion Moxibustion at CV 8 can reduce the serum MDA and BNU levels as well as the activity of AST, ALT and LDH of organism in a status of long-term fatigue, effectively improve the symptom of long-term fatigue, providing a certain experimental basis for the clinical application of moxibustion at CV 8 in the process of anti-exercise-induced fatigue in the future.

Experimental study on the effect of moxibustion at Shenque(CV 8) for long-term exercise-induced fatigue

Objective:To investigate the effect of moxibustion at Shenque(CV 8)on fatigue in rats with chronic exercise-induced exhaustion.Methods:Thirty male Sprague-Dawley(SD)rats were randomly divided into a blank group,a model group and a moxibustion group,10 rats in each group.Except rats in the blank group,the remaining rats were subjected to create long-term exhaustion models by repeated swimming.After successful modeling,rats in the moxibustion group received mild moxibustion at Shenque(CV 8)for 15 min,once every other day with a total of 10 times.Rats in the model group and the blank group did not receive moxibustion.At the end of the treatment,the exhausted times,and the body weight of rats before and after the experiment were compared among groups.The levels of blood malondialdehyde(MDA)and urea nitrogen(BUN),as well as the activities of aspartate transarninase(AST),alanine aminotransferase(ALT)and lactate dehydrogenase(LDH)were also measured by the automatic biochemical analyzer,24 h after the exhausting excise.Results:The 10 th swimming time was significantly longer in the moxibustion group than that in the model group(P〈0.01).The increase rate of the body weight was lower in the rats of the moxibustion group than that in the model group before the 7 th and the 10 th exhausting excise(P〈0.05,P〈0.01).The levels of serum MDA and BUN,as well as the activities of AST,ALT and LDH in the model group were higher than those in the blank group(all P〈0.01).The levels of serum MDA and BUN,as well as the activities of AST,ALT and LDH in the moxibustion group were lower than those in the model group(P〈0.01).Conclusion:Moxibustion at Shenque(CV 8)can decrease the serum levels of MDA and BUN,as well as activities of AST,ALT and LDH in the long-term fatigue rats,thus to improve the symptoms of fatigue.

Effect of moxibustion at Shenque （CV 8） on free radical metabolism in rat＇s hippocampus after different degrees of exhaustive exercise

Objective： To investigate the effect of moxibustion at Shenque （CV 8） on free radical metabolism in rat＇s hippocampus after different degrees of exhaustive exercise. Methods： A total of 72 male Sprague-Dawley （SD） rats were randomly divided into a normal group （n=8）, a model group （n=32） and a moxibustion group （n=32）. According to the times of modeling or treatment, the model group was further randomly divided into different subgroups of a 1-time model subgroup, a 4-time model subgroup, a 7-time model subgroup and a 10-time model subgroup （n=8）; the moxibustion group was also further randomly divided into different subgroups of a 1-time moxibustion subgroup, a 4-time moxibustion subgroup, a 7-time moxibustion subgroup and a 10-time moxibustion subgroup （n=8）. Rats in both model and moxibustion subgroups were subjected to establishing the swimming exhaustive model. Rats in each moxibustion subgroup received mild moxibustion at Shenque （CV 8） for 15 min immediately after modeling, once every other day. The concentration of malic dialdehyde （MDA）, as well as the activities of superoxide dismutase （SOD）, glutathione peroxidase （GSH-Px） and total antioxidant capacity （T-AOC） in rat＇s hippocampus in each group were detected 24 h after the exhaustive exercise. Results： Compared with the 1-time model subgroup, the exhaustive swimming time of rats was significantly prolonged in the 4-time model subgroup （P〈0.01）, while it was significantly shortened in the 7-time and 10-time model subgroups （both P〈0.01）. Compared with the matched model subgroup, the exhaustive swimming time of rats in the 7-time and 10-time moxibustion subgroups was significantly prolonged （both P〈0.01）. Compared with the normal group, the MDA concentration was increased significantly （P〈0.01）, and the activities stress response of SOD and T-AOC were increased in the 1-time model subgroup （both P〈0.05）; the MDA concentration was increased （all P〈0.01）, and the activities of SOD, GSH-Px and T-AOC were decreased differently （P〈0.05 or P〈0.01） in the 4-time, 7-time and 10-time model subgroups. Compared with the matched model subgroup, the concentration of MDA was significantly reduced （P〈0.05 or P〈0.01）, and the activities of SOD, GSH-Px and T-AOC were significantly increased in the 4-time, 7-time and 10-time moxibustion subgroups （all P〈0.01）. Conclusion： Moxibustion at Shenque （CV 8） can improve the fatigue status of the body after long-term exhaustive exercise by regulating free radical metabolism in rat＇s hippocampus. To some extent, this provides an experimental basis for moxibustion at Shenque （CV 8） against exercise-induced fatigue.