高中物理第二章能的转化与守恒2.3能量守恒定律教学设计鲁科版必修2课件

1、C. Some slangs have been accepted.D. English slangs have different meanings actually.60. Which of the following is the best title for the passage?A. You can change the English language.B. English is changing over years.C. The British speaks differently from Americans.D. Foreign words involved in Eng

2、lish.BWe've all experienced a "good cry". Shedding (流 some tears can often make us feel better and help us see things right. But why is crying beneficial? And is there such a thing as a "bad cry"?The researchers analyzed the detailed accounts of more than 3,000 recent crying

3、experiences and found that the benefits of crying depend entirely on the what, where and when of a particular crying episode (一段经历. The majority of persons reported improvements in their mood following a short period of crying. However, one third reported no improvement in mood and a tenth felt wors

4、e after crying. Criers who received social support during their crying episode were the most likely to report improvements in mood.Research to date has not always produced a clear picture of the benefits of crying, in part because the results often seem to depend on how crying is studied. The resear

5、chers note several challenges in accurately studying crying behavior in a laboratory setting. Volunteers who cry in a laboratory setting often do not describe their experiences as making them feel better. Rather, crying in a laboratory setting often results in the study participants feeling worse; t

6、his may be due to the stressful conditions of the study itself, such as being videotaped or watched by researchers. This may produce negative emotions, which neutralize (使无效 the positive benefits usually connected with crying.However, these laboratory studies have provided interesting findings about

7、 the physical effects of crying. Criers do show calming effects such as slower breathing, but they also experience a lot of unpleasant stress, including increased heart rate and sweating. What is interesting is that bodily calming usually lasts longer than the unpleasant. The calming effects may occ

8、ur later and overcome the stress reaction, which would account for why people tend to remember mostly the pleasant side of crying.Research has shown that the effects of crying also depend on who is shedding the tears. For example, individuals with anxiety or mood disorders are least likely to experi

9、ence the positive effects of crying. In addition, the researchers report that people who lack insight into their emotional lives actually feel worse after crying.61. We can infer from the passage that _.A. people don't like being seen cryingB. crying in public makes people feel betterC. a bad cr

10、y is as common as a good cryD. a good cry can sometimes help us face problems rightly62. The beneficial effects of crying can be shown when _.A. your breath becomes slow B. you sweat a lot.C. your face turns pale D. you are being watchedA. People who receive help in course of crying.B. People who fa

11、il to understand their emotions.C. People who are anxious and nervous.D. People whose mood is not in order.A. their problems are understood by othersB. their stress is got rid of more or lessC. their heart is beating fasterD. they find a chance to show anger65. The passage is mainly about _.A. the t

12、ypes of crying B. the way of cryingC. the psychology of crying D. the causes of cryingCWomen are a lot more likely to suffer a broken heart than men, researchers say. The good news is that it probably won't kill you. In the first national study of its kind, researchers at the University of Arkan

13、sas looked at rates of "broken heart syndrome" when a sudden shock or lasting stress causes heart attack-like symptoms or heart failure and found that it especially affects women.Women are at least seven times more likely than men to suffer the syndrome, and older women are at greater risk

14、 than younger ones, according to data presented Wednesday at the American Heart Association conference in Orlando. "It's the only cardiac(心脏的 condition where there's such a female preponderance," Dr. Abhiram Prasad, a Mayo Clinic cardiologist who was not associated with the study,

15、told the AP. Heart attack and heart disease, of course, strike men more often and earlier in life than women.Broken heart syndrome can happen in response to shocking or suddenly emotional events both positive ones like winning the lottery, or negative ones like a car accident or the unexpected death

16、 of a loved one. A flood of stress hormones and adrenaline(荷尔蒙与肾上腺素 causes part of the heart to enlarge temporarily and triggers symptoms that can look like heart attack: chest pain, shortness of breath, irregular heart rhythm. The difference is that the factors that would normally cause heart attac

17、k, such as a blocked artery（动脉）, aren't present.One theory is that hormones play a role. Another is that men have more adrenaline receptors on cells in their hearts than women do, "so maybe men are able to handle stress better" and the chemical surfeit (过量releases, Deshmukh said. About

18、 10% of sufferers will have a second episode at some point, but most return to full heart function without permanent damage or need for follow-up treatment. So, it looks like the way to mend a broken heart is what Mom always said: just give it time.66. What is the finding of the searchers at the Uni

19、versity of Arkansas according to the passage?A. Men have the equal chance to suffer a broken heart.B. A lot of people are killed by heart attack.C. Women are more likely to suffer a broken heart than men.D. Younger women are more likely to suffer a broken heart.67. Which of the following is not like

20、ly to cause the broken heart syndrome?A. a car accident B. having a good sleepC. winning the lottery D. unexpected death of a loved one68. What is the heart attack-like symptom?A. Brain pain B. Shortness of breathC. A blocked artery D. Regular heart rhythm69. What can you infer from the last paragra

21、ph?A. Hormones play a role in causing heart attack.B. It takes long to recover from the broken heart.C. Men are able to handle stress better than women.D. Heart attack-like symptoms cause permanent damage.70. The passage is most probably found in the column of .A. entertainment of a magazine B. fash

22、ion of magazineC. life of a newspaper D. reference of a guidebook for doctorsPart IV Writing (45 marksSection A (10 marksDirections: Read the following passage. Fill in the numbered blanks by using the information from the passage.Write NO MORE THAN THREE WORDS for each answer.The United Nations est

23、imates that world food production will have to increase by 70% by 2050. A world population growing in number and wealth will require one billion tons more grain each year, and two hundred million tons more meat.The Food and Agriculture Organization says those gains will have to happen largely on exi

24、sting land. However, according to a new report which provides the first "global assessment of the state of the planet's land resources" , large parts of all continents are experiencing damage. One-fourth of all land is described as "highly degraded(退化 ". The greatest threats

25、are losses of soil quality, biodiversity and water resources. Therefore, production rates have been slowing in many areas. Though new agricultural methods and technology are used to increase food production in many countries, yet they have also harmed the land and water. Thus, it calls for greater u

26、se of ways that can expand production while avoiding damage to ecosystems.One such practice might be the use of "fertilizer trees." These are fast-growing trees and shrubs （矮树丛） whose leaves and roots help make soil richer.Oluyede Ajayi, the leader author of the study, said "Basically

27、 these are trees that can fix nitrogen(氮 from the atmosphere and change them into nitrates （硝酸盐） for fertilizer, for organic fertilizer, for the soil."The farmers who planted fertilizer trees reported double the corn production of other farmers. In Zambia, the fertilized fields provided up to 1

28、14 additional days of food. Farmers say they need less rainwater if they use fertilizer trees. The trees reduce water runoff and soil erosion.A recent study found that about 400,000 farmers in southern Africa are using them. The farmers themselves designed and managed part of the testing in the fiel

29、d, and spread the word of their successes.Fertilizer trees can be used to increase food productionProblems World population growth 71 the increase of world food production Large parts of global land 72 by losses of soil quality and water3.多媒体课件：物体在不同的力学条件下的运动At home, I told my mom my experience and

30、told her my idea. My mom agreed with me. I found a few clothes and went back to the drug store. When I got there, I didnt hand the clothing over myself. I wanted it to be a secret, so I asked someone to hand the clothes over, then I left. As I left, I heard someone saying “thank you!” and I hoped it

31、 was for me.On the road, my heart was full of happiness and warmth. I felt glad that I could share something on my birthday and that was a big gift for me.81. Why did the writer cry on his way to the drug store?(No more than 13 words (2 marks82. What is the writers purpose of going to the drugs stor

32、e? (No more than 7 words (2 marks83. How did the writer help the beggars son? (No more than 8 words (3 marks84. What did the writer think of what he did for the beggars son? (No more than 10 words (3 marksSection C (25 marks提出问题：上述运动过程中，物体的机械能是否变化呢？这是我们本节要探究的主要内容。注意：1. 报道应包括图表所示全部内容，可适度发挥；2. 词数不少于12

33、0 个。Dear editor,I have recently made a survey among 60 students in my class about their purpose of surfing on the Internet.参考答案:1-15 BCABA CCABC BABAC16. New/Five Computer Courses 17. Name(of courses 18. Using Software二82. Buying some Vitamin for his mom.83. By donating some smaller clothes to him.8

34、4. He felt that was a big gift for him.参考范文：Dear editor,I have recently made a survey among 60 students in my class about their purposes of surfing on教师提出以下几种情景：1.只有重力对物体做功时物体的机械能情景1：质量为m的物体自由下落过程中，经过高度h1的A处速度为v1，下落至高度h2的B处速度为v2，不计空气阻力，分析由h1下落到h2过程中机械能的变化(引导学生思考分析。情景2；从倾角为的光滑斜面上滑下的小车，经过A点时速度为va，下滑位移

35、S，到达B点速度为vb。分析此过程机械能的变化.2.弹簧和物体组成的系统的机械能.情景3.以弹簧振子为例(未讲振动，不必给出弹簧振子名称，只需讲清系统特点即可，简要分析系统势能与动能的转化。教师要求与启发：要求学习小组选择一个情景，用学过的动能定理，重力的功与重力势能变化的关系，对以上前两种情景，定量写出物体经历的过程前后的机械能E1和E2，看机械能变化了没有，存在什么关系。第三种情景要求定性分析。(三学习小组理论探究结果展示与讨论情景1小组理论探究结果展示的内容：根据动能定理，有 WG=mv22-mv12 下落过程中重力对物体做功，重力做功在数值上等于物体重力势能的变化量。取地面为参考平面，

36、有WGmgh1-mgh2 由以上两式可以得到mv22+ mgh2 =mv12+ mgh1 情景2小组理论探究结果展示的内容：下滑过程中重力对物体做功，重力做功在数值上等于物体重力势能的变化量。取B点重力势能为零，有WGmghsin 根据动能定理，有 WG=mvB2-mvA2 =m(vB2- vA2 =m×2as=m×2gssin=mgssin 提出问题：上述结论是否具有普遍意义呢？(作为课后作业，请同学们课后进一步分析物体做平抛和竖直上抛运动时的情况。学生讨论：上述两个表达式说明了什么？讨论后、学习小组代表回答。代表甲：在表达式中等号左边是物体在A处的机械能，等号右边是物体在B处的机械能，该表达式说明：物体在下落过程中，物体的机械能总量不变。代表乙：对于表达式，重力做的功等于动能的增量，也等于重力势能的减少量。该表达式说明：