2022年人教版八年级上册物理知识点总结 3.pdf

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1、exchange experience in safety, commend advanced teams and indivi duals; 8, the establishment of the workshop safety management network, regular checking, arrangement of security work, workshop and team security officer role into full play9, issued strict enforcement of labor protection articles, hea

2、lth sta ndards, and do a good job post workers labor protection wear, guara nteed post workers safety and health; 10, develop emergency plans and drills are regularly organized. Assistant Superintendent of security responsibilities 1, Director of the workshop on the safety of the unit responsible, D

3、e puty Director i n charge of business-wide security work; 2, seriously carry out the party and the countrys work safety laws, regulations, standards, and research on safety technology, exemplary in the implementation of operational procedures and Safety Manager. 10, develop emergency plans and dril

4、ls are regularly organized. Group leaders safety duties 1 and carry out business and workshop on safety instructions and requirements, the teams overall responsibility for the safety and personal safety and health of workers; 2 organize and participate in security activities, adhere to safety, befor

5、e class to check security, after summing up the se curity system; 3, responsible for new workers (including internships, accompanying staff) job safety, education and the right to stop without the third-level education and safety assessment of qualified workers operate independently; 4, found acci d

6、ents signs and acci dents take effective measures to prevent the situation from expandi ng and reporting; shall immediately report the accident and organized rescue, prote ct the scene, make detailed records, participate in acci dent investigations, organize workers to analyze the cause of the accid

7、ent, the implementation of preventive measures; 5, engaging in obvious danger or serious violations of the employee shall be entitled to stop the operation of the procedures and arra ngements post operator, report to the leadership; 6 so as to improve safety and fire fighting facilities, equi pment

8、inspections and maintenance work, remain flexible to use, check the worker reasonable use of personal protective equipment, and proper use of fire fighting equipment. 7, focus on team-building, improve management level of teams. Keep the work site tidy, clean, realization of civilization, and do ide

9、ological and political work team; 8 so as to improve track safety contest, commend the advanced experiences. Craft safety responsibilities 1, responsible for their own safety in the context of work, ensure the safety and reliability of the technical work. 2, is responsible for the preparation of tec

10、h nical spe cifications for the units security and safety management system. In the preparation of start up, shut down, or whe n e quipment maintenance, technical feasibility, to have reliable health and safety measures and inspection of the implementation. 3, in the area of staff security technique

11、 and safety training, organization of technical training activities, regular assessment. 4, often goes into the field to checkproduction safety situation, potential accident is discovered in time to propose measures to eliminate them, to stop illegal operations. Do not scatter in an emergency, to st

12、op their work, and to immediately report to the management. 5 participate in workshop equipment, changes in technol ogy programme and review of roasting temperature curve s modified, to comply with safety requirements and product requirements. 6 participate in any accident investigation, analysis, a

13、 nd find out the reason, responsibility and come up with preventive measures, and shall promptly report to the leadership or author ity. 7, making maintenance, shutdown, work programme, in particular w hen process cha nges, mapping work well before start. Level 1 employee safety responsibilities, co

14、nscientiously study the relevant safety instructions, rules and safety procedures, mastering the post operating rules; 2, must wear PPE as required operation, proper use and proper st orage of protective equipment and fire-fighting equi pment; 3, work will focus on safety, stable operati on and stri

15、ctly observe labour discipline and process discipline a nd conscientiously records, gang, leave, is strictly prohibited in the post, not sleepi ng, slapstick a nd other di sci plinary matters, to discourage the illegal actions of others and . 2, responsible for fire analysis and enter the Tower, tan

16、ks of gas metering and analysis data reported to the authorities. 3, responsible for accident investigation, statistics and reporting work. 1 electrical safety responsibilities, conscientiously study a nd abide by the safety rules and regulations, in strict compliance with the prohibitions and provi

17、sions of safety, perform guard duties. 2, before the operation, wear appropriate PPE, implement security measures, issuing safety permits, inspection tools, instruments are in good conditi on. 3, any electrical applia nce without inspection, shall be deemed to have access to electricity, is forbidde

18、 n to touch. 4, electrical maintena nce, you must stop, cut off power, and hang up the no close warning signs before they can work. 5, good job in electricity, maintenance records, easily lead to key parts of ongoing supervision and inspection of the accident.第一章声现象一、声音的产生与传播：1、声音是由物体的振动产生的。举例：人靠声振带

19、动发声、蜜蜂靠翅膀下的小黑点振动发声，风声是空气振动发声，管制乐器靠里面的空气柱振动发声，弦乐器靠弦振动发声，鼓靠鼓面振动发声，钟靠钟振动发声等。2、振动停止，发声停止；但声音并没立即消失。解释：因为原来发出的声音仍在继续传播，发声的物体一定振动，有振动不一定能听见声音。3、发声体可以是固体、液体和气体。4、声音的振动可记录下来，并且可重新还原（唱片的制作、播放）5、声音的传播需要介质；固体、液体和气体都可以传播声音；一般情况下，声音在固体中传得最快，气体中最慢；6、真空不能传声，月球上（太空中）的宇航员只能通过无线电话交谈；7、声音以声波的形式传播；8、声速：物体在每秒内传播的距离叫声速，单

20、位是m/s；声速的大小跟介质的种类和温度有关；声速的计算公式是v=s/t ；声音在15的空气中的速度为340m/s；9、回声：听见回声的条件：原声与回声之间的时间间隔在0.1s 以上（教室里听不见老师说话的回声，狭小房间声音变大是因为原声与回声叠加重合，听见回声的最小距离为17m ） ；回声的利用：测量距离（车到山的距离，海的深度，冰川到船的距离）；二、我们怎样听到声音：1、人耳的构成：人耳主要由外耳道、鼓膜、听小骨、耳蜗及听觉神经组成；2、听到声音正常传播途径：外界传来的声音引起鼓膜振动，这种振动经听小骨及其他组织传给听觉神经，听觉神经把信号传给大脑，人就听到了声音. 3、耳聋的分类：鼓膜、

21、听小骨处出现障碍是传导性耳聋；听觉神经处出障碍是神经性耳聋。4、骨传导：靠头骨、颌骨传给听觉神经，再传给大脑形成听觉。例子：贝多芬耳聋后听音乐、我们说话时自己听见的自己的声音。（注：骨传导的性能比空气传声的性能好。）5、双耳效应：声源到两只耳朵的距离一般不同，因而声音传到两只耳朵的时刻、强弱及步调也不同。应用：判断声源方位的现象。（我们听见立体声就属于双耳效应的应用）三、声音的三个特征1、音调：人感觉到的声音的高低。音调跟发声体振动频率有关，频率越高音调越高；频率越低音调越低。（物体在1s 振动的次数叫频率，物体振动越快频率越高。频率单位次/ 秒又记作Hz）2、超声波和次声波：人耳感受声音频率

22、有一个范围：20Hz20000Hz，高于 20000Hz 叫超声波；低于20Hz叫次声波；应用：次声波有大象靠次声波交流、地震、火山爆发、台风、海啸产生次声波；超声波有猫狗等动物听觉、B超等。3、响度：人耳感受到的声音的大小。响度跟发生体的振幅和距发声距离的远近有关。（物体在振动时，偏离原来位置的最大距离叫振幅。）振幅越大响度越大。增大响度的主要方法是：减小声音的发散。4、音色：由物体本身决定。应用：人们根据音色能够辨别乐器或区分人、可以看西瓜熟没、瓷碗的好坏等。四、噪声的危害和控制1、当代社会的四大污染：噪声污染、水污染、大气污染、固体废弃物污染。2、物理学角度，噪声是指发声体做无规则的杂乱

23、无章的振动发出的声音；环境保护的角度，噪声是指妨碍人们正常休息、学习和工作的声音，以及对人们要听的声音起干扰作用的声音。3、人们用分贝（dB）来划分声音等级：听觉下限0dB；为保护听力应控制噪声不超过90dB；为保证工作学习，应控制噪声不超过70dB；为保证休息和睡眠应控制噪声不超过50dB 。4、减弱噪声的方法：在声源处减弱、在传播过程中减弱、在人耳处减弱。五、声音的利用1、传递信息（医生查病时的“闻”，打 B超；敲铁轨听声音；超声波基本沿直线传播用来回声定位制作声纳等等）2、传递能量（飞机场旁边的玻璃被震碎；雪山中不能高声说话；一音叉振动，未接触的音叉振动发声；超声波的能量大频率高可用来打

24、结石、清洗钟表等精密仪器）第二章光现象一、光的传播：1、光源：本身能够发光的物体。精选学习资料 - - - - - - - - - 名师归纳总结 - - - - - - -第 1 页，共 11 页exchange experience in safety, commend advanced teams and indivi duals; 8, the establishment of the workshop safety management network, regular checking, arrangement of security work, workshop and team

25、security officer role into full play9, issued strict enforcement of labor protection articles, health sta ndards, and do a good job post workers labor protection wear, guaranteed post workers safety and health; 10, develop emergency plans and drills are regularly organized. Assistant Superintendent

26、of security responsibilities 1, Director of the workshop on the safety of the unit responsible, De puty Director i n charge of business-wide security work; 2, seriously carry out the party and the countrys work safety laws, regulations, standards, and research on safety technology, exemplary in the

27、implementation of operational procedures and Safety Manager. 10, develop emergency plans and drills are regularly organized. Group leaders safety duties 1 and carry out business and workshop on safety instructions and requirements, the teams overall responsibility for the safety and personal safety

28、and health of workers; 2 organize and participate in security activities, adhere to safety, before class to check security, after summing up the se curity system; 3, responsible for new workers (including internships, accompanying staff) job safety, education and the right to stop without the third-

29、level education and safety assessment of qualified workers operate independently; 4, found acci dents signs a nd acci dents take effective measures to prevent the situation from expandi ng and reporting; shall immediately report the accident and organized rescue, prote ct the scene, make detailed re

30、cords, participate in acci dent investigations, organize workers to analyze the cause of the accident, the implementation of preventive measures; 5, engaging in obvious danger or serious violations of the employee shall be entitled to stop the operation of the proce dures and arra ngements post oper

31、ator, report to the leadership; 6 so as to improve safety and fire fighting facilities, equi pment inspections and maintenance work, remain flexible to use, check the worker reasonable use of personal protective equipment, and proper use of fire fighting equipment. 7, focus on team-building, improve

32、 management level of teams. Keep the work site tidy, clean, realization of civilization, and do ideological and political work team; 8 so as to improve track safety contest, commend the advanced experiences. Craft safety responsibilities 1, responsible for their own safety in the context of work, en

33、sure the safety and reliability of the technical work. 2, is responsible for the preparation of technical spe cifications for the units security and safety management system. In the preparation of start up, shut down, or whe n e quipment maintenance, technical feasibility, to have reliable health an

34、d safety measures and inspection of the implementation. 3, in the area of staff security technique and safety training, organization of technical training activities, regular assessment. 4, often goes into the field to checkproduction safety situation, potential accident is discovered in time to pro

35、pose measures to eliminate them, to stop illegal operations. Do not scatter in an emergency, to stop their work, and to immediately report to the management. 5 participate in w orkshop equipment, cha nges in technol ogy programme and review of roasting temperature curve is modified, to comply with s

36、afety requirements and product requirements. 6 participate in any accident investigation, analysis, a nd find out the reason, responsibility and come up with preventive measures, and shall promptly report to the leadership or author ity. 7, making maintenance, shutdown, work programme, in particular

37、 w hen process cha nges, mapping work well before start. Level 1 employee safety responsibilities, conscientiously study the relevant safety instructions, rules and safety procedures, mastering the post operating rules; 2, must wear PPE as required operation, proper use and proper st orage of protec

38、tive equipment and fire-fighting equi pment; 3, work will focus on safety, stable operation and strictly observe labour discipline and process discipline and conscientiously records, gang, leave, is strictly prohibited in the post, not sleepi ng, slapstick a nd other di sci plinary matters, to disco

39、urage the illegal actions of others and . 2, responsible for fire analysis and enter the Tower, tanks of gas metering and analysis data reported to the authorities. 3, responsible for accident investigation, statistics and reporting work. 1 electrical safety responsibilities, conscientiously study a

40、 nd abide by the safety rules and regulations, in strict compliance with the prohibitions and provisions of safety, perform guard duties. 2, before the operation, wear appropriate PPE, implement security measures, issuing safety permits, inspection tools, instruments are in good conditi on. 3, any e

41、lectrical applia nce without inspection, shall be deemed to have access to electricity, is forbidde n to touch. 4, electrical maintenance, you must stop, cut off power, and hang up the no close warning signs before they can work. 5, good job in electricity, maintenance records, easily lead to key pa

42、rts of ongoing supervsion and inspection of the accident.2 分类：人造光源（如电灯、点燃的火把、油灯、燃烧的蜡烛等）自然光源（太阳、水母、萤火虫、恒星）说明：光源指的是自身能发光的物体，不包括反射光的情况。如月亮是靠反射太阳的光、自行车的尾灯、公路上的交通标志牌及放电影时的银幕的光等。2、光在同一种均匀介质中沿直线传播。说明：如果介质不均匀，即使在同一种介质中，光的传播路线也会发生弯曲。如地球周围的大气层是不均匀的，海拔越高，空气越稀薄，太阳光进入大气层后，传播方向就会发生弯曲，早晨当太阳还在地平线以下时，我们就看见它了。3、光线：光线

43、并不是真实存在的，而是为形象、直观的表示光的传播路线和方向，方便研究光学现象而假设虚构的，是一种理想化的物理模型。4、常见关于光直线传播的现象：激光准直影子的形成：光在传播过程中，遇到不透明的物体，在物体的后面形成黑色区域即影子。日食月食的形成：当地球在中间时可形成月食。小孔成像：成倒立的实像，其像的形状与孔的形状无关。5、光速：光是宇宙中最快的使者，在真空中的速度C=3108m/s=3105km/s。说明：光在其它介质中的传播速度比在真空中的速度小，在水中的速度约为真空中光速的3/4 ，在玻璃中速度为真空中速度的2/3 。规律总结：光能在真空中传播，而声音不能在真空中传播。二、光的反射定律：

44、1、定义：光从一种介质射向另一种介质表面时，一部分光被反射回原来介质的现象叫光的反射。2、概念：入射点（入射光线与反射面的交点）、入射光线（射向反射面的光线）、反射光线（从反射面反射出去的光线） 、法线（经过入射点所做的反射面的垂线）、入射角（入射光线与法线的夹角）、反射角（反射光线与法线的夹角）、3、光的反射定律：反射光线与入射光线、法线在同一平面上，反射光线和入射光线分居于法线的两侧，反射角等于入射角。光的反射过程中光路是可逆的。拓展： A当入射光线垂直射向平面镜时，反射光线沿原路返回，反射光线、入射光线与法线重合，即三线合一。此时，入射角、反射角均为0 度。 B 光路可逆原理误区警示：反

45、射角和入射角的逻辑关系：因为先有入射光线，然后才有反射光线；所以，在光的反射定律中，我们不能说入射角等于反射角，只能说反射角等于入射角。三、平面镜成像1、平面镜成像特点：物体在平面镜里所成的像是虚像。像、物到镜面的距离相等。像、物大小相等。像、物的连线与镜面垂直。2、平面镜成像原理：光的反射定理。3、实像和虚像：实像：实际光线会聚点所成的像。虚像：反射光线反向延长线的会聚点所成的像。4、平面镜成像的作图问题一般分为两类：已知平面镜、物体和像的三者中的两者的位置关系，求剩余一项的位置。此种类型的问题，我们可以根据平面镜成像的特点来作图求可见范围，此种类型问题，我们可以利用光的反射规律和平面镜成像

46、的特点来作图。规律总结：作图的方法有两种：光的反射定律和平面镜成像规律，具体用哪种方法，要根据题目的要求。根据平面镜成像规律作图，先要确定像的位置；根据光的反射定律作图，先要画出法线。5、分类：镜面反射：定义（射到物面上的平行光反射后仍然平行）条件：反射面平滑。应用：迎着太阳看平静的水面，特别亮。黑板“反光”等，都是因为发生了镜面反射漫反射：定义（射到物面上的平行光反射后向着不同的方向，每条光线遵守光的反射定律。）条件：反射面凹凸不平。应用：能从各个方向看到本身不发光的物体，是由于光射到物体上发生漫反射的缘故。四、光的折射现象1、定义：光从一种透明介质斜射入另一种透明介质时，在两种物质的分界面

47、上，光线的传播方向一般会发生改变，一部分光线返回原来的介质，发生反射现象，另一部分进入另一种介质中发生折射现象。因此光的折射现象就是光从一种介质斜射入另一介质时，传播方向一般会发生变化的现象。2、光的折射定律： 折射光线， 入射光线和法线在同一平面内。折射光线和入射光线分居与法线两侧。光从空气斜射入水或其他介质中时，折射角小于入射角，属于近法线折射。光从水中或其他介质斜射入空气中时，折射角大于入射角，属于远法线折射。光从空气垂直射入（或其他介质射出） ，折射角 =入射角 = 0 度。在折射时光路是可逆的。精选学习资料 - - - - - - - - - 名师归纳总结 - - - - - - -

48、第 2 页，共 11 页exchange experience in safety, commend advanced teams and indivi duals; 8, the establishment of the workshop safety management network, regular checking, arrangement of security work, workshop and team security officer role into full play9, issued strict enforcement of labor protection a

49、rticles, health sta ndards, and do a good job post workers labor protecti on wear, guaranteed post workers safety and health; 10, develop emergency plans and drills are regularly organized. Assistant Superintendent of security responsibilities 1, Director of the workshop on the safety of the unit re

50、sponsible, Deputy Director in charge of business-wide security work; 2, seriously carry out the party and the countrys work safety laws, regulations, standards, and research on safety technology, exemplary in the implementation of operational procedures and Safety Manager. 10, develop emergency plan