nyuuzyou/kompy huggingface dataset:
Why students procrastinate - Student Procrastination: Why Students Procrastinate and How to Stop It

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Student Procrastination: Why Students Procrastinate and How to Stop It
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bet | 3/10 | Sana | 23.12.2023 | Hajmi | 31,98 Kb. | | #127460 |
Bog'liq Student Procrastination
Students procrastinate because issues like exhaustion and anxiety outweigh their self-control and motivation. These issues include personal factors, like fear and perfectionism, and situational factors, like distractions and unclear instructions.
Specifically, when students need to study or work on assignments, they rely primarily on their self-control in order to get themselves to do it. Furthermore, their self-control is sometimes supported by their motivation, which helps them do things in a timely manner.
However, in some cases, students suffer from various issues that interfere with or oppose their self-control and motivation, such as exhaustion and anxiety. When these issues are stronger than their self-control and motivation, they end up procrastinating, until they reach a point where the balance between these factors shifts in the students’ favor, or until it becomes too late.
This explains why many students procrastinate in a chronic manner even when they have the necessary motivation and truly want to study and get their work done. This also explains why many students always procrastinate on academic work until right before the deadline, at which point the increased motivation, often in the form of stressful pressure, finally pushes them to start studying or to start working on their assignments.
Accordingly, common reasons why students procrastinate include the following:
Abstract goals, generally in terms of being vague about when and how the students intend to study or do their work.
Feeling overwhelmed, often while being unsure of how to deal with the academic task at hand.
Perfectionism, generally in the form of refusing to create work that has any flaws.
Fear of failure, often due to concerns over how failure might reflect on the student’s abilities and skills, either in their eyes or in the eyes of others.
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Identify your productivity cycles

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Identify your productivity cycles
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bet | 6/10 | Sana | 23.12.2023 | Hajmi | 31,98 Kb. | | #127460 |
Bog'liq Student ProcrastinationIdentify your productivity cycles. Students vary in terms of when they’re most productive; for example, some work best in the morning, while others are more focused at night. You should take this into account, and schedule your study and work to times of day when you’re least likely to procrastinate.
Improve your environment:
Change your environment to make it harder for yourself to procrastinate. For example, if you tend to procrastinate on writing essays because you keep browsing social media, turn off your internet connection on your computer before you get to work.
Change your environment to make it easier for yourself to get started. For example, if you know that you’ll need to study for an exam tomorrow morning, organize all the relevant study material on your desk or in your bag before you go to bed.
Change your environment to make it easier for you to keep going. For example, if you know that you’re likely to lose concentration if you get distracted while studying, go study in a quiet room and leave your phone outside.
Change your approach:
Start with a tiny step. For example, if you need to write an essay, help yourself get started by committing to only write a single sentence at first. This can help you push yourself to get started on tasks, and often, once you do so, you’ll find it easy to keep going.
Start with the best or worst part first. Some students find that starting with the most enjoyable or easiest part of an assignment helps them get going, while others find that getting the worst part out of the way first helps them avoid procrastinating over time. You can use either approach if you find that it works well for you.
Add a time delay before you procrastinate. If you can’t avoid procrastinating entirely, try committing to having a time delay before you indulge your impulse to do so. For example, this can involve counting to 10 before you’re allowed to open a new tab on the social media website that you usually use to procrastinate.
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Use the Pomodoro technique - Student Procrastination: Why Students Procrastinate and How to Stop It

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Student Procrastination: Why Students Procrastinate and How to Stop It
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bet | 7/10 | Sana | 23.12.2023 | Hajmi | 31,98 Kb. | | #127460 |
Bog'liq Student ProcrastinationUse the Pomodoro technique. This involves alternating between scheduled periods of study and rest. For example, you can study for 25-minute long stretches, with 5-minute breaks in between, and a longer 30-minute break after every 4 study sets that you complete.
Increase your motivation:
Make studying feel more rewarding. For example, you can gamify your studying, by marking down streaks of days on which you’ve managed to achieve your study goals, and potentially also giving yourself some reward once you reach a sufficiently long streak.
Make studying feel more enjoyable. For example, if studying in your room is uncomfortable, try going somewhere more pleasant, such as the library.
Visualize your future self. For example, you can visualize yourself being able to relax after finishing an assignment, visualize yourself being rewarded for getting a good grade, or visualize yourself having to handle the issues associated with not studying enough.
Focus on your goals instead of on your tasks. For example, if you need to work on an assignment that you find boring, then instead of focusing on the assignment, try thinking about your academic goals and about the reason why you want to do well on that assignment, such as that you want to get a good grade in the class so you can have a stronger college application.
Change your mindset:
Give yourself permission to make mistakes. For example, if you’re working on an assignment, accept the fact that your work likely won’t be perfect, especially at first. Furthermore, you can decide to start by just getting some initial answers written down, and then go over your work at the end to check if you need to make corrections.
Address your fears. If you’re procrastinating because you’re afraid of something, try to identify your fears and resolve them. For example, if you’re afraid that your writing won’t be good enough, you can say to yourself that your goal is to just start by getting something written down, and that you can always improve it later.
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Develop self-compassion - Student Procrastination: Why Students Procrastinate and How to Stop It

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Student Procrastination: Why Students Procrastinate and How to Stop It
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bet | 8/10 | Sana | 23.12.2023 | Hajmi | 31,98 Kb. | | #127460 |
Bog'liq Student ProcrastinationDevelop self-compassion. Self-compassion can help reduce your procrastination, as well as various issues that are associated with it, such as stress. It consists of three components that you should promote: self-kindness, which involves being nice to yourself, common humanity, which involves recognizing that everyone experiences challenges, and mindfulness, which involves accepting your emotions in a non-judgmental manner.
Develop self-efficacy. Self-efficacy is the belief in your ability to perform the actions needed to achieve your goals. It can help you reduce your procrastination, as well as associated issues, such as anxiety. To develop self-efficacy, try to identify the various strategies that you can use to successfully study and complete your assignments, and think about your ability to execute those strategies successfully.
You’ll probably need to use multiple techniques in order to reduce your procrastination, but even just a few should help. Start with just a few techniques initially, to avoid getting overwhelmed, and then you can add more techniques over time, based on your progress.
If you suffer from an underlying issue that causes procrastination, such as ADHD, depression, or lack of sleep, you will likely need to resolve that issue first, using professional help if necessary, in order to successfully overcome your procrastination.
Overall, to stop procrastinating on your schoolwork, you should identify the smallest possible thing you can do to make progress on it, and then modify your environment to make it as likely as possible that you will do it. In the long term, you should also figure out the causes of your procrastination, and use relevant anti-procrastination techniques, like setting concrete goals, breaking tasks into manageable steps, and giving yourself permission to make mistakes.
How to help students stop procrastinating
When it comes to helping students overcome their procrastination, for example if you’re a teacher or a parent, there are three main approaches that you can use:
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Anxiety, often in light of potential negative feedback.
 
Task aversion

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Anxiety, often in light of potential negative feedback.
Task aversion
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bet | 4/10 | Sana | 23.12.2023 | Hajmi | 31,98 Kb. | | #127460 |
Bog'liq Student ProcrastinationAnxiety, often in light of potential negative feedback.
Task aversion, especially in cases where the students find an assignment boring or unpleasant.
Lack of motivation, often as a result of not caring about academic performance, feeling disconnected from their future self, or having rewards that are too far in the future.
Physical or mental exhaustion, often due to a combination of reasons, such as a high academic workload together with lack of sleep.
Resentment, generally toward the studying or assignments directly, toward their source, or toward something related, such as a parent pushing the student to do well in a subject that they’re not interested in.
Sensation seeking, generally in the form of enjoying working on things right before the deadline, when there’s intense time pressure that can make otherwise boring assignments more challenging and exciting.
Problematic work environment, generally as a result of having many distractions or temptations around.
Lack of sufficient communication from instructors, for example when it comes to not having clear directions and due dates for a certain class project.
Other common causes of student procrastination include behaviors such as self-handicapping, which involves procrastinating so that if the student fails then they can blame their failure on procrastination rather than on their abilities, and self-sabotaging, which involves procrastinating as a result of a tendency to hinder one’s progress.
Furthermore, certain personality traits, such as distractibility and impulsivity, are associated with the tendency to procrastinate, meaning that people who are naturally high in these traits are more likely to procrastinate.
Finally, there are also some underlying issues that can lead to procrastination, like ADHD, depression, and lack of sleep.
Overall, students procrastinate because issues such as exhaustion and anxiety outweigh their self-control and motivation. Common issues that lead to student procrastination include abstract goals, feeling overwhelmed, perfectionism, fear of failure, task aversion, resentment, a problematic work environment, and sensation seeking.
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An externally led approach - Student Procrastination: Why Students Procrastinate and How to Stop It

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Student Procrastination: Why Students Procrastinate and How to Stop It
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bet | 9/10 | Sana | 23.12.2023 | Hajmi | 31,98 Kb. | | #127460 |
Bog'liq Student ProcrastinationAn externally led approach. This involves using relevant anti-procrastination techniques to reduce students’ procrastination, without actively involving them in the process. For example, this can involve setting a series of intermediate project deadlines for all students in a course.
A student-led approach. This involves letting students overcome their procrastination with little to no external guidance. External guidance in this case might include something as minimal as mentioning the problem of procrastination and telling students about a relevant resource such as this article.
A joint approach. This involves giving students external guidance while also encouraging them to take an active role in their attempts to stop procrastinating. For example, this can involve going over relevant anti-procrastination techniques with students, and helping them choose and implement their preferred ones.
None of these approaches is inherently superior to the others. Accordingly, you should decide which one to use based on factors such as the number of students that you’re trying to help and the type of relationship that you have with them. For example, if you’re a teacher trying to help 200 students in a college course you will likely need to use a different approach than if you’re a parent trying to help just your kid.
Almost any type of relationship can be beneficial when it comes to helping a student overcome their procrastination. For example, if you’re a teacher, you’re likely in a good position in terms of your influence over the student’s academic situation. On the other hand, if you’re a parent, you’re likely in a good position in terms of your influence over the student’s home life.
Furthermore, you can reach out to other stakeholders who can help. For example, if you’re a teacher, and you think that a student’s parents might be able to help them stop procrastinating, you can reach out to them and discuss the situation.
In addition, an important factor to keep in mind is how independent the students in question are. In general, the more independent students are, the more they should be involved in the process of overcoming their procrastination, since this can increase their motivation and make the process more effective, while generally leading to more self-development and growth over time. This also raises the importance of giving students a sense of control, even if you’re the one guiding the process, which can be especially crucial when it comes to avoiding procrastination that’s rooted in issues such as resentment, rebellion, or lack of self-confidence.
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Bipolyar tranzistorli elektron kalit sxemalar

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Bipolyar tranzistorli elektron kalit sxemalar
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bet | 3/4 | Sana | 20.05.2024 | Hajmi | 10,59 Kb. | | #245068 |
Bog'liq Bipolyar tranzistorlarning tuzilishi, ishlashi, ulanish sxemaslaBipolyar tranzistorli elektron kalit sxemalar.
BT da yasalgan sodda kalit sxemasi 4 – rasmda keltirilgan. Yuklama qarshiligi RK emitteri umumiy shinaga ulangan tranzistorning kollektor zanjiriga ulangan. Kalit ikkita turg‗un holatga ega bo‗lishi kerak: ochiq va berk. Ochiq kalit holatiga tranzistorning to‗yinish yoki aktiv ish rejimi, berk holatga esa - berkilish rejimi mos keladi. Agar tranzistor bazasiga manfiy kuchlanish berilsa (Ukir0V), u holda emitter va kollektor o‗tishlar teskari yo‗nalishda ulangan bo‗ladi, ya‘ni berk holatda bo‗ladi. Bu vaqtda tranzistor kollektor tokining berkilish rejimida ishlaydi va kalit uzilgan holatda bo‗ladi. Berkilish rejimida tranzistor toklari mos ravishda
Ie 0 , Ik = Iko , Ib = -Iko .
Natijada tranzistor kollektoridagi kuchlanish
Uk = Uchiq = Em – Iko * Rk Em.
Bo’lib, yuklamaning manbadan uzilgan holatiga mos keladi (kalit uzilgan). Baza zanjirida Rb rezistor mavjud bo’lganda tranzistor baza kuchlanishi
Ub = Ube = -Ukir + Iko * Rb.
4-rasm. Bipolyar tranzistorli elektron kalit sxemalar.
Yuqori temperaturalarda kalit Iko qiymati keskin ortadi va natijada emitter o’tishdagi kuchlanish ham ortadi. Shu sababli berkilish rejimida tranzistor normal ishlashi uchun quyidagi shart bajarilishi kerak
bu yerda UBO‘S – emitter o’tishdagi musbat kuchlanish UBE bo’lib, ushbu qiymat ortsa tranzistor berk rejimdan aktiv rejimga o’tadi, ya‘ni ochiladi. Integral texnologiyada bajarilgan kremniyli tranzistorlar uchun
UBO‘S = 0,50,6 V.
Agar UKIR=0, u holda shart quyidagicha qayta yoziladi.
Iko * Rb U bo’s .
UBO‘S=0,6 V va IK0=1mkA deb faraz qilsak, u holda RB.max=0,6 MOm ga teng bo’ladi. Kirishga UKIR0,7 V (mantiqiy bir U1 ) kuchlanish berilsa tranzistor aktiv yoki to‗yinish rejimida ishlaydi (kalit ulangan).
Kalit rejimda tranzistorning aktiv ish rejimi ma‘qullanmaydi, chunki yuklamadagi tok faqat yuklama Rk va manba kuchlanishi YeM kattaligi bilan emas, balki tranzistordagi kuchlanish pasayishi UKE bilan ham aniqlanadi,
Shunday qilib, agar kalit kirishiga mantiqiy nol potensiali berilsa, u holda uning chiqishida mantiqiy birga mos potensial hosil bo‗ladi va aksincha, ya‘ni bunday kalit invers sxema hisoblanadi va invertor deb ataladi.
Sxema iste‘mol qilayongan tok ortsa, sig’imlarning katta qayta zaryadlanish tezligi hisobiga qayta ulanish vaqti ortadi. Lekin bu vaqtda sxemaning iste‘mol quvvati ortadi. Shu sababli o’rtacha kechikish vaqti qayta ulanish ishi AQ=RtK deb ataluvchi kattalik bilan aniqlanadi.
Xulosa
Men “Sanoat elektronikasi” fanidan “Bipolyar transiztorlarning tuzilishi,ishlashi va ulanish sxemalari” mavzusi bo’yicha mustaqil ish tayyorlab bipolyar tranzistorlar, bipolyar tranzistorlarning ulanish sxemalari va bipolyar tranzistorlarning elektron kalit sxemalari haqida ma’lumotga ega bo’ldim.
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FOYDALANILGAN ADABIYOTLAR - Bipolyar tranzistorlarning tuzilishi, ishlashi, ulanish sxemaslari. Reja

X.K. Aripov, A.M. Abdullaev, N.B. Alimova. Elektronika. O’quv qo’llanma– Toshkent: TATU, 2008, 137 b.
Ugryumov Ye.P. «Tsifrovaya sxemotexnika». Sankt-Peterburg «BXV - Peterburg» 2007g.
Bezugmov D.А., Kalenko I.V. «Tsifroviye ustroyistva i mikroprotsessoriy». Rostov na Donu 2006 g.
Babich N.P., Jukov I.А., «Osnoviy tsifrovoy sxemotexniki» Moskva, DMK, Press2007 g.
Yu.F. Opadchiy, O.P. Gludkin, A.I. Gurov. Analogovaya i sifrovaya elektronika. – M.: Goryachaya liniya – Telekom, 2003.
Stepanenko I.P. Osnovi mikroelektroniki: Uchebnoe posobie dlya vuzov. – 2-e izd., pererab. i dop.- M.: Laboratoriya Bazovix Znaniy, 2001.
Yu.L. Bobrovskiy, S.A. Kornilov, I.A. Kratirov i dr.; Pod red. prof. N.F. Fedorova. Elektronnie, kvantovie pribori i mikroelektronika: Uchebnoe posobie dlya vuzov.- M.: Radio i svyaz, 2002.
Laboratoriya shınıǵıwı №12 Tema: Aerosúwretler menen islesiw, deshifrovkalaw Shiniǵiwdiń bilim beriw maqseti

Laboratoriya shınıǵıwı №12 Tema: Aerosúwretler menen islesiw, deshifrovkalaw Shiniǵiwdiń bilim beriw maqseti
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Bosh sahifa
Aloqalar Bosh sahifa Laboratoriya shınıǵıwı №12 Tema: Aerosúwretler menen islesiw, deshifrovkalaw Shiniǵiwdiń bilim beriw maqseti
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Windows oilasi operatsion tizimi tarixi imkoniyatlari ishchi stol elementlari

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Windows oilasi operatsion tizimi tarixi imkoniyatlari ishchi stol elementlari
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Sana | 06.12.2023 | Hajmi | 40,44 Kb. | | #112895 |
Bog'liq Axborot 14 Windows oilasi operatsion tizimi tarixi imkoniyatlari ishchi stol elementlari Reja: 1.Windows ishchi stol elementlari bilan tanihish. 2.Fayl va papka ustida amallar. Windows ishchi stol elementlari bilan tanihish. Windows ishchi stol elementlari bilan tanihish. Bosh menyu(Пуск) ko`rinishi 2 xil: Меню «Пуск», Классическое меню «Пуск». Bosh menyuni qisqacha tuzilishi quyidagicha: Документы – Oxirgi 15 ta ishlatilgan fayllar ro`yhati; Настройка – Windows konfiguratsiyasi va qurilmalarini o`rnatish va sozlash; Найти – Ma’lumotlar va ob’yektlarni izlash; Справка и поддержка – Windows yordam ma’lumotlar bloki; Fayl va kataloglar bilan ishlash. Fayllarni ko`chirish va nusxasini olish uchun quyidagilarni bajarish kerak: Fayl va kataloglar bilan ishlash. Fayllarni ko`chirish va nusxasini olish uchun quyidagilarni bajarish kerak: - Nusxasi olinadigan va ko`chiriladigan faylni ajratish. - Oynadagi Asboblar panelidan nusxa olish uchun “Buferga nusxasini ko`chirish” (Copy) asbobini, ko`chirish uchun esa Вырезать/Сut-”Buferga ko`chirish” asbobini tanlash. - Fayl nusxasi joylashtiriladigan qurilma yoki papkani tanlash. - “Asboblar paneli”dan “Buferdan olib qo`yish” (Paste) asbobini tanlash. Fayl nomini o`zrartirish Moy komp’yuter yoki Provodnik oynalarida quyidagilarni bajarish kerak: - Nomi o`zgartiriladigan fayl yoki papka tanlanadi. - Fayl nomi yoki papka nomi ustida “sichqoncha” tugmasi bir marta bosiladi. - Yangi nom klaviatura yordamida kiritiladi. Bajardi: Jurayeva Farangiz Raxmiddin qizi!!! Bajardi: Jurayeva Farangiz Raxmiddin qizi!!!
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Texnologik jarayon tavsifi. Kirish chiqish kattaliklari

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Texnologik jarayon tavsifi. Kirish chiqish kattaliklari
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bet | 5/14 | Sana | 07.12.2023 | Hajmi | 1,12 Mb. | | #113426 |
Bog'liq Jaxongir1.2.Texnologik jarayon tavsifi. Kirish chiqish kattaliklari
Gazlarni tozalash ikki bosqichda o’tkaziladi. Tozalashga kiritiluvchi gaz separatorga berilib, undan kondensat ajratiladi. Separator yuqorisidan chiquvchi gaz adsorberga yuboriladi. Separator (lotincha “separator” – “ajratkich”) gazdan suyuq va qattiq zarralarni, suyuqlikdan qattiq zarralarni ajratish, qattiq yoki suyuq aralashmalarni tarkibiy qismlarga ajratish uchun mo`ljallangan qurilma. Neft va Gaz Separatori esa neftli aralashma tarkibidan neftni va gazni ajratib beruvchi qurilmadir.
3-rasm. Gorizantal separator sxemasi
Gaz separatorning yuqori qismi orqali chiqarib tashlanadi. PIRC-220 rostlagichi undagi bosimni gazlarni chiqarib tashlash quvurida (truboprovodida)gi klapan yordamida ushlab turadi. FIR-120 datchigi gaz sarfini o‘lchaydi, AIR-520 analizatori gaz fazasidagi butan miqdorini nazorat qiladi.
Suyuq faza separatorning tubi orqali separatorda berilgan sathni ta’minlab turuvchi LIRC-410 rostlagich klapani joylashgan quvur (truboprovod) bo‘yicha chiqariladi. TIR-310 datchigi separatordagi haroratni, FIR-110 datchigi separatordan ketayotgan sarfni, AIR-510 analizator-suyuq fazadagi butan miqdorini nazorat qiladi.
Ishchi diapazon chegarasidan jarayonning asosiy o‘zgaruvchilari chiqib ketganda, ogohlantiruvchi yoki avariyali signalizasiya ishlab ketadi.
Bosimni avariyali pasaytirish uchun NGS separatorda baypasida NS-010 rostlanuvchi qulfi bo`lgan saqlagich klapan o`rnatilgan.
Saqlagich klapan bosim 3 kg/sm2 bo‘lganda ochiladi.
1.3. Funksional texnologik sxemaning tavsifi
Gkir [m3/soat] – Kirishda neft sarfi;
Рkir[atm] – Kirishda neft bosimi;
Lkir [%] – separatorda neft sarfi;
GNchiq[m3/soat]- chiqishda neft sarfi;
GGchiq[m3/soat]- chiqishda gaz sarfi.
V [m3] – separator hajmi.
Separatorda ketayotgan jarayonni keyingi tekshirishlar uchun, jarayonning statistik modelini ishlab chiqish kerak.
Ob`ektga nisbatan chapda joylashgan parametrlar kirish parametrlari, ya`ni o`zgartirish mumkin bo`lgan parametrlar. Ularning qiymati jarayon rejimiga bog`liq emas deb faraz qilinadi.
Obektga nisbatan o`ngda joylashgan parametrlar-chiqish parametrlari, ya`ni ularning qiymati kirish parametrlari ta`siriga bog`liq ravishda boshqarish va g`alayon parametrlari ta`siri ostida jarayonning o`zgarish rejimi asosida aniqlanadi.
Ob`ektga nisbatan yuqorida joylashgan parametrlar-jarayonning o`zgarmas qiymatlari, yoki ob`yektning texnologik konstantalari
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Pedagogika” fanidan kursish I mavzu: Ta’lim jarayoni yagona pedagogic tizim sifatida. Ta’lim tamoyillari

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Pedagogika” fanidan kursish I mavzu: Ta’lim jarayoni yagona pedagogic tizim sifatida. Ta’lim tamoyillari
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bet | 1/37 | Sana | 24.05.2024 | Hajmi | 1,01 Mb. | | #251920 |
Bog'liq 1BT Xolova Qunduz
O’ZBEKISTON RESPUBLIKASI OLIY TA’LIM FAN VA INNOVATSIYA VAZIRLIGI
Buxoro Davlat Pedagogika Instituti
Boshlang’ich va Maktabgacha ta’lim fakulteti
Boshlang’ich ta’lim kafedrasi
“Pedagogika” fanidan
K U R S I S H I
Mavzu: Ta’lim jarayoni yagona pedagogic tizim sifatida. Ta’lim tamoyillari.
Bajardi: 1BT-22S guruh talabasi Xolova Qunduz
(imzo) (ism sharif)
Kurs ishi himoya qiling an sana “____” __________ 2024 yil
Baho “___” ___________________
Ilmiy rahbar:
(imzo) (ism sharif)
Komissiyaa’zolari: _______________________________
(imzo) (ism sharif)
__________________________________________________
(imzo) (ism sharifi)
Buxoro-2024
Boshlang’ich ta’lim kafedrasi
“Pedagogika” fanidan
KURS IShI UChUN TAQRIZ
Guruh 1BT-22S
Talaba familiyasi va ismi-sharifi Xolova Qunduz
Kurs ishi mavzusi: Ta’lim jarayoni yagona pedagogic tizim sifatida. Ta’lim tamoyillari.
Kurs ishining tarkibi.................................................……………………
Kurs ishi himoyasida talabaga berilgan savollar ro'yxati:.....................................
................................................................................................................................
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…………………………………………………………………………………….
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Jadval va grafik materialning miqdori (muhim chizmalarning ko'rsatgichi)..............................................................................................................
Kurs ishining ijobiy tomonlari.................................................................................
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Kurs ishining kamchiliklari.....................................................................................
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Kurs ishiga qo'yilgan baho......................................................................................
Kurs ishiga rahbarning ismi-sharifi va imzosi.......................................................
…………………………………………………………………………………….
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Toshkent davlat transport universiteti “Transportda axborot tizimlari

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Toshkent davlat transport universiteti “Transportda axborot tizimlari
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bet | 1/5 | Sana | 17.11.2023 | Hajmi | 0,6 Mb. | | #100524 |
Bog'liq 4-LABORATORIYA. KOMPYUTERDA QO‘SHIMCHA OT NI YUKLASH UCHUN VIRTUAL BOX DASTURINI QO‘LLASH.
TOSHKENT DAVLAT TRANSPORT UNIVERSITETI
“Transportda axborot tizimlari va texnologiyalari”
kafedrasi
TIZIMLI DASTURIY TA’MINOT
fanidan
4 – laboratoriya ishi
Bajardi: ATM-7 guruh talabasi
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Berdiyeva A
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Qabul qildi:
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Aliyev M.M.
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Тоshkent -2023
№4 Laboratoriya
MAVZU: KOMPYUTERDA QO‘SHIMCHA OT NI YUKLASH UCHUN VIRTUAL BOX DASTURINI QO‘LLASH.
Ishdan maqsad: Bir kompyuterda bir necha operatsion tizimni yuklash va sozlashni o‘rganish.
Laboratoriya ishlarini bajarish uchun topshiriqlar
1.Uslubiy ko‘rsatma bilan batafsil tanishing
2.Dasturni o‘rnatish va sozlash.
3.Qo‘shimcha OTni “VirtualBox” dasturi orqali yuklash.
Qo‘shimcha OTni yuklash uchun kompyuterlarni virtual tarzda ishlatish imkonini beruvchi, Oracle VM VirtualBox dasturini o‘rnatish, sozlash talab etiladi. VirtualBox dastur bepul xisoblanadi va bir nechta tillarda ishlaydi. Dasturni InnoTek korxonasi 2007 yili ishlab chiqargan. 2008 yili Sun Microsystem korxonasi uni sotib olgan va xozirgacha uni takomillashtirish bilan shug‘ullanadi. Ushbu dastur xozirgi kundagi deyarli barcha OT (Windows, Linux/Unix, Mac OS) larni virtual ravishda o‘z kompyuteringizda ishlatish imkonini beradi.
VirtualBox ning imkoniyatlari:x86-virtualizatsiya;
ko‘p-yadroviy va ko‘p protsessorlik imkoniyatlari;
audio qurilmalar bilan ishlash;
USB-xostlarni virtualizatsiyasi;
ishlash tezligi yuqoriligi va shu bilan birga kompyuter resurslariga talabi baland emasligi;
xar xil turdagi tarmoq ulanishlar bilan ishlash (NAT, Host Network, Bridge, Internal);virtual kompyuterlarni xolatlarini "rasmga" olib ularni saqlab qo‘yish imkoniyati (snapshots), va ularga virtual kompyuterni ortga qaytarish mumkinligi;
VirtualBoxdasturini sozlash va boshqarishni buyruqlar yordamida cmd orqali boshqarish imkoniyati.
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Balans sxemalari asosidagi kuchaytirgichlar

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Balans sxemalari asosidagi kuchaytirgichlar
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bet | 6/6 | Sana | 22.01.2024 | Hajmi | 0,92 Mb. | | #142936 |
Bog'liq 10-MA\'RUZA10.3. Balans sxemalari asosidagi kuchaytirgichlar - 10.3. Balans sxemalari asosidagi kuchaytirgichlar
- Yakka kuchaytirgich bosqichlarini manfiy teskari zanjiri orqali bosqichlash yo‘li bilan keng polosali kuchaytirgichlarni integral usulda yasashda yaxshilash mumkin.
- Bir vaqtning o‘zida balans sxemalar asosida qurilgan kuchaytirgichlarda xarakteristikalar sezilarli yaxshilanishi kuzatiladi.
- Bu turdagi kuchaytirgichlarda kirish bosqichi sifatida balans turli sodda sxemalar – differensial kuchaytirgichlar (parallel – balansli yoki farqli). Ular ishining yuqori barqarorligi va kichik nol dreyfi bilan ajralib turadi.
- Balans sxema ishlash prinsipini to‘rt yelkali ko‘prik sxema misolida tushuntirish mumkin (5 - rasm).
- 5 – rasm
- Agar ko‘prik balans sharti bajarilsa, ya’ni u holda yuklama qarshiligi RYu da tok va mos ravishda kuchlanish nolga teng bo‘ladi. Kuchlanish manbai qiymati va ko‘prik yelkasidagi rezistorlar qarshilik qiymatlari o‘zgarsa ham balans buzilmaydi, faqat rezistor qarshiliklari nisbati o‘zgarishsiz qolsagina.
Bitta tranzistorda bajarilgan kuchaytirgich bosqichlarida kollektor (emitter) yuklamalarida signalga bog‘liq bo‘lmagan kuchlanish ajraladi. Bu kuchlanish manba qiymati o‘zgarsa, qizish natijasida tranzistor toklari qiymatlari o‘zgarsa va boshqa ta’sirlar natijasida o‘zgaradi va bu bilan kuchaytirish qurilmasi parametrlarini barqarorligini pasaytiradi. - Bitta tranzistorda bajarilgan kuchaytirgich bosqichlarida kollektor (emitter) yuklamalarida signalga bog‘liq bo‘lmagan kuchlanish ajraladi. Bu kuchlanish manba qiymati o‘zgarsa, qizish natijasida tranzistor toklari qiymatlari o‘zgarsa va boshqa ta’sirlar natijasida o‘zgaradi va bu bilan kuchaytirish qurilmasi parametrlarini barqarorligini pasaytiradi.
- Elementar kuchaytirish bosqichlariga nisbatan differensial kuchaytirgich dinamik xarakteristikalarini barqaror tok generatori hisobiga uning ish rejimini barqarorlash yordamida amalga oshirish ham mumkin.
Nazorat savollari. - Nazorat savollari.
- Kuchaytirgich deb nimaga aytiladi?
- Kuchlanish kuchaytirgichini tushuntiring?
- Tok kuchaytirgichi deb nimaga aytiladi?
- Quvvat kuchaytirgichini ta’riflang?
- Chiziqli buzilishlar nimalar?
- O‘zgarmas tok kuchaytirgichlari deb nimaga aytiladi?
- Integral keng polosali kuchaytirgichlarga nimalar kiradi?
- Tanlov kuchaytirgichlari (filtrlar) deb nimaga aytiladi?
- Balans sxemalari asosidagi kuchaytirgichlarni tushuntiring?
ETIBORINGIZ UCHUN RAHMAT
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Bipolyar tranzistorning ulanish sxemalari

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Bipolyar tranzistorning ulanish sxemalari
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bet | 2/4 | Sana | 20.05.2024 | Hajmi | 10,59 Kb. | | #245068 |
Bog'liq Bipolyar tranzistorlarning tuzilishi, ishlashi, ulanish sxemaslaBipolyar tranzistorning ulanish sxemalari
BTda elektrodlar uchta bo'lgani sababli, uch xil ulanish sxemalari mavjud: umumiy baza (UB) , umumiy emitter (UE) , umumiy kollektor (UK) (2-rasm). Bunda ВТ elektrodlaridan biri sxemaning kirish va chiqish zanjirlari uchun umumiy, uning o'zgaruvchan tok (signal) bo'yicha potensiali esa nolga teng qilib olinadi. BTning 2-rasmda keltirilgan ulanish sxemalari aktiv rejimga mos.
2-rasm. BTning statik rejimda umumiy baza (a), umumiy emitter (b) va umumiy kollektor (d) ulanish sxemalari.
Kuchlanish manbai qutblari va tranzistor toklarining yo‗nalishi tranzistorning aktiv rejimiga mos keladi. UB ulanish sxemasi qator kamchiliklarga ega bo’lib, juda kam ishlatiladi. Har bir ulanish uchun statik xarakteristikalar oilasi ma‘lumotnomalarda keltiriladi. Eng asosiylari bo‗lib tranzistorning kirish va chiqish xarakteristikalari hisoblanadi. Qolgan xarakteristikalar kirish va chiqish xarakteristikalaridan hosil qilinishi mumkin. UB sxemasi uchun kirish statik xarakteristikasi bo’lib U = const bo’lgandagi I= f (U) bog’liqlik, U sxemasi uchun esa U = const bo’lgandagi I=f(U) bog‗liqlik hisoblanadi. Kirish xarakteris-tikalarining umumiy xarakteri odatda to’g’ri yo’nalishda ulangan p-n bilan aniqlanadi. Shu sababli tashqi ko’rinishiga ko’ra kirish xarakteristiklari eksponensial xarakterga ega (3- rasm).
3-rasm.Bipolyar transiztorlarning I=f(U) bog’liqlik xarakteristikasi.
Bipolyar tranzistorlarning xususiy xossalari asosiy bo’lmagan zaryad tashuvchilarning baza orqali uchib o’tish vaqti va o’tishlarning to’siq sig’imlarining qayta zaryadlanish vaqti bilan aniqlanadilar. Juda kichik kirish signallari va aktiv ish rejimi uchun bipolyar tranzistorni chiziqli to’rtqutblik ko’rinishida ifodalash mumkin va bu to’rtqutblikni biror parametrlar tizimi bilan belgilash mumkin. Bu parametrlarni h–parametrlar deb atash qabul qilingan. Ularga quyidagilar kiradi: h11 – chiqishda qisqa tutashuv bo’lgan vaqtdagi tranzistorning kirish qarshiligi; h12 - uzilgan kirish holatidagi kuchlanish bo’yicha teskari aloqa koeffisienti; h21 - chiqishda qisqa tutashuv bo’lgan vaqtdagi tok bo’yicha kuchaytirish (uzatish) koeffisienti; h22-uzilgan kirish holatidagi tranzistorning chiqish o’tkazuvchanligi. Barcha h – parametrlar oson va bevosita o’lchanadi. Elektronika bo’yicha avvalgi adabiyotlarda kichik signalli parametrlarning chastotaviy bog’liqliklariga juda katta e‘tibor qaratilgan. Hozirgi vaqtda 10 GGs gacha bo’lgan chastotalarda normal ishni ta‘minlaydigan tranzistorlar ishlab chiqarilmoqda. Bunday xollarda talab qilinayotgan chastota xarakteristikalarini olish uchun ma‘lumotnomadan kerakli tranzistor turini tanlash kerak.
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Komplementar emitter qaytargich

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Komplementar emitter qaytargich
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bet | 5/6 | Sana | 22.01.2024 | Hajmi | 0,92 Mb. | | #142936 |
Bog'liq 10-MA\'RUZA - 10.2. Komplementar emitter qaytargich
- 3 – rasmda komplementar tranzistorlarda: VT1 – tranzistor n-p-n turli va VT2 – tranzistor p-n-r turli bajarilgan V sinfiga mansub sodda ikki taktli chiqish bosqichi sxemasi keltirilgan. Yuklama tranzistorlarning emitter zanjiriga ulanadi, demak ular kuchlanish qaytargichlari rejimida ishlaydilar. Quvvat kuchayishi tok kuchayishi bilan amalga oshiriladi. Ikki qutbli kuchlanish manbalari (+EM va –EM) qo‘llanilganiga alohida e’tibor qaratamiz. Shu sababli sokinlik rejimida ikkala tranzistor berk holatda bo‘ladi, chunki emitter o‘tishlardagi kuchlanish nolga teng bo‘ladi. Natijada, sokinlik rejimida sxema energiya iste’mol qilmaydi.
Kirishga Rkir signalning musbat yarim davri berilsa VT1 ochiladi va RYu yuklama orqali 1 strelka yo‘nalishida tok oqib o‘tadi. Manfiy yarim davr mobaynida p-n-r turli tranzistor ochiladi va tok 2 strelka yo‘nalishida oqib o‘tadi. Quvvat kuchaytirish koeffisienti taxminan emitter va baza toklari nisbatiga teng bo‘ladi - Kirishga Rkir signalning musbat yarim davri berilsa VT1 ochiladi va RYu yuklama orqali 1 strelka yo‘nalishida tok oqib o‘tadi. Manfiy yarim davr mobaynida p-n-r turli tranzistor ochiladi va tok 2 strelka yo‘nalishida oqib o‘tadi. Quvvat kuchaytirish koeffisienti taxminan emitter va baza toklari nisbatiga teng bo‘ladi
Lekin, V turli kuchaytirgich bo‘la turib, sxema katta nochiziqli buzilishlar koeffisientiga ega (KG>10 %). Bu kamchilikni bartaraf etish maqsadida kuchaytirgich murakkablashtiriladi. R1 va R2 rezistorlar, hamda VD1 va VD2 diodlar yordamida tranzistor bazalariga individual siljish kiritiladi (4 - rasm). Natijada dastlabki ishchi nuqta ikkala tranzistor ozgina ochiq holatdagi (AV rejim) sohada joylashadi, lekin ulardan A turli kuchaytirgichlardagiga nisbatan ancha kichik tok oqib o‘tadi. - Lekin, V turli kuchaytirgich bo‘la turib, sxema katta nochiziqli buzilishlar koeffisientiga ega (KG>10 %). Bu kamchilikni bartaraf etish maqsadida kuchaytirgich murakkablashtiriladi. R1 va R2 rezistorlar, hamda VD1 va VD2 diodlar yordamida tranzistor bazalariga individual siljish kiritiladi (4 - rasm). Natijada dastlabki ishchi nuqta ikkala tranzistor ozgina ochiq holatdagi (AV rejim) sohada joylashadi, lekin ulardan A turli kuchaytirgichlardagiga nisbatan ancha kichik tok oqib o‘tadi.
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Nazorat savollari - Toshkent davlat transport universiteti “Transportda axborot tizimlari

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Toshkent davlat transport universiteti “Transportda axborot tizimlari
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bet | 3/5 | Sana | 17.11.2023 | Hajmi | 0,6 Mb. | | #100524 |
Bog'liq 4-LABORATORIYA. KOMPYUTERDA QO‘SHIMCHA OT NI YUKLASH UCHUN VIRTUAL BOX DASTURINI QO‘LLASH.Nazorat savollari
OT va drayver dasturlari nima?
OT va drayver dasturlari qanday o‘rnatiladi?
OT klassifikatsiyalarini sanab bering?
Javoblar:
1. OT va drayver dasturlari nima?
Drayver — bu OT asosiy bo'lagi bo'lib, uni sodda qilib tushuntirsak, u OT ga bog'langan barcha fizik qurilmalarning so'zlarini OT ga tarjima qiluvchi yoki OT buyruqlarini qurilmalarga tarjima qiluvchi kichik dastur hisoblanadi. Demak drayverlar ham dastur ekaligini bilib oldik. Endi bu qurilmalarga nima kirishi mumkin deyishingiz mumkin, Kompyuteringiz ishlashi uchun nima va qanday qurilma kerak bo'lsa bularning barchasi kiradi ya'ni protsessor (ona plata ichida joylashgan miya), operativ xotira, doimiy xotira, videa grafika, kalonka, tarmoq kartasi, kuller, shinalar, blok-pitaniya, usb va h.klardir. Bundan tashqari qo'shimcha drayverlar mavjud ya'ni printer qurilmasining drayveri, mobil telefonlarni kompyuterga ulash uchun ishlatiluvchi drayverlar va boshqalar bo'lishi mumkin. Drayverlar orqali OT ishi yengillashadi ya'ni OT to'g'ridan to'g'ri qurilmaga murojaat qilmasdan uning drayveriga murojaat qiladi va drayver o'zining qurilmasi bilan aloqani o'rnatib, OT yuklagan vazifalarni yetkazib beradi.
Drayverlar
Qo'shimcha dasturlar — bu OT va uning drayverlari o'rnatilgandan so'ng OT ishga tayyor bo'lgandan so'ngina o'rnatiluvchi, foydalanuvchiga yordamlashuvchi, qandaydir masala bo'yicha ko'maklashuvchi dasturlar hisoblanadi. Bunday dasturlar juda ko'p bo'lib, ularning turi ham ko'rinishi ham ko'pdir. Bular OT ga murojaat qiladi OT esa bu dastur uchun kerakli qurilmadan keraklicha joy ajratib beradi (albatta drayverlar yordami bilan) va bu dastur ishlashi uchun sharoit yaratib beradi. Agar OT dastur so'rayotgan qo'llab-quvvatlashga javob bera olmasa bu dastur ishga tushmaydi va qanday kamchilik yuzaga kelsa shuni ogohlantirish oynasi orqali ekranga chiqazadi. Bu kabi dasturlarga MS Office paketi, Google chrome brauzeri, Total Commander, WinRAR kabi dasturlarni misol qilib keltirish mumkin.
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O‘zgarmas tok kuchaytirgichlari

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O‘zgarmas tok kuchaytirgichlari
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bet | 4/6 | Sana | 22.01.2024 | Hajmi | 0,92 Mb. | | #142936 |
Bog'liq 10-MA\'RUZA O‘zgarmas tok kuchaytirgichlari deb tok va kuchlanishning nafaqat o‘zgaruvchan, balki o‘zgarmas tashkil etuvchilarini ham kuchaytirishga mo‘ljallangan qurilmalarga aytiladi. Bunday kuchaytirgichlarning past chastotasi nolga teng, yuqori chastotasi esa juda katta (bir necha o‘n MGs) bo‘ladi. O‘zgarmas tok kuchaytirgichlarining turlari ko‘p (differensial, operasion kuchaytirgichlar, signal o‘zgartiruvchi kuchaytirgichlar va boshqalar). - O‘zgarmas tok kuchaytirgichlari deb tok va kuchlanishning nafaqat o‘zgaruvchan, balki o‘zgarmas tashkil etuvchilarini ham kuchaytirishga mo‘ljallangan qurilmalarga aytiladi. Bunday kuchaytirgichlarning past chastotasi nolga teng, yuqori chastotasi esa juda katta (bir necha o‘n MGs) bo‘ladi. O‘zgarmas tok kuchaytirgichlarining turlari ko‘p (differensial, operasion kuchaytirgichlar, signal o‘zgartiruvchi kuchaytirgichlar va boshqalar).
- Integral keng polosali kuchaytirgichlar berilgan past chastotadan yuqori chegaraviy chastotagacha bo‘lgan keng chastota diapazonidagi signallarni kuchaytiradilar.
Tanlov kuchaytirgichlari (filtrlar) deb berilayotgan signallar majmuidan ma’lum chastota spektridagi sinusoidal shaklga ega bo‘lganlarini tanlab, ularni kuchaytiradigan kuchaytirgichlarga aytiladi. Tanlov kuchaytirgichlari maxsus shakldagi AChX ga egadirlar. - Tanlov kuchaytirgichlari (filtrlar) deb berilayotgan signallar majmuidan ma’lum chastota spektridagi sinusoidal shaklga ega bo‘lganlarini tanlab, ularni kuchaytiradigan kuchaytirgichlarga aytiladi. Tanlov kuchaytirgichlari maxsus shakldagi AChX ga egadirlar.
- Signalni kuchaytirish amalga oshiriladigan chastotalar oralig‘i, o‘tkazish polosasi deb ataladi. Signallar so‘ndiriladigan chastota polosasi chegaralovchi chastota deb ataladi. O‘tkazish va chegaralovchi chastotalarning o‘zaro joylashishiga ko‘ra quyidagi tanlov kuchaytirgichlari turlari mavjud: past chastota, yuqori chastota, polosali o‘tkazuvchi, polosali chegaralovchi. Filtrlar RC zanjirlar va aktiv elementlar asosida amalga oshiriladi. Shuning uchun ular aktiv filtrlar deb ataladi.
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Chiziqli buzilishlar - Kuchaytirgichlarning asosiy parametrlari va xarakteristikalari

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Kuchaytirgichlarning asosiy parametrlari va xarakteristikalari
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bet | 3/6 | Sana | 22.01.2024 | Hajmi | 0,92 Mb. | | #142936 |
Bog'liq 10-MA\'RUZAChiziqli buzilishlar esa tranzistor parametrlarining chastotaga bog‘liqligidan aniqlanadi. Kuchaytirgichning chastota xususiyatlari amplituda-chastota xarakteristikasi (AChX) dan aniqlanadi. AChX deganda kuchaytirish koeffisientining chastotaga bog‘liqligi tushuniladi. Ideal AChX gorizontal chiziq hisoblanadi. Real AChX esa kamayuvchi sohalarga ega bo‘ladi. 2 – rasmda normallashtirilgan AChXChiziqli buzilishlar esa tranzistor parametrlarining chastotaga bog‘liqligidan aniqlanadi. Kuchaytirgichning chastota xususiyatlari amplituda-chastota xarakteristikasi (AChX) dan aniqlanadi. AChX deganda kuchaytirish koeffisientining chastotaga bog‘liqligi tushuniladi. Ideal AChX gorizontal chiziq hisoblanadi. Real AChX esa kamayuvchi sohalarga ega bo‘ladi. - Chiziqli buzilishlar esa tranzistor parametrlarining chastotaga bog‘liqligidan aniqlanadi. Kuchaytirgichning chastota xususiyatlari amplituda-chastota xarakteristikasi (AChX) dan aniqlanadi. AChX deganda kuchaytirish koeffisientining chastotaga bog‘liqligi tushuniladi. Ideal AChX gorizontal chiziq hisoblanadi. Real AChX esa kamayuvchi sohalarga ega bo‘ladi. 2 – rasmda normallashtirilgan AChXChiziqli buzilishlar esa tranzistor parametrlarining chastotaga bog‘liqligidan aniqlanadi. Kuchaytirgichning chastota xususiyatlari amplituda-chastota xarakteristikasi (AChX) dan aniqlanadi. AChX deganda kuchaytirish koeffisientining chastotaga bog‘liqligi tushuniladi. Ideal AChX gorizontal chiziq hisoblanadi. Real AChX esa kamayuvchi sohalarga ega bo‘ladi.
2 – rasmda normallashtirilgan AChX keltirilgan. Bu yerda K0 – nominal kuchaytirish koeffisienti, ya’ni kuchaytirish koeffisienti o‘zgarmas bo‘lgan chastota sohalari. Odatda chastota buzilishlarining ruxsat etilgan koeffisient kattaligi 3 dB dan oshmaydi. - 2 – rasmda normallashtirilgan AChX keltirilgan. Bu yerda K0 – nominal kuchaytirish koeffisienti, ya’ni kuchaytirish koeffisienti o‘zgarmas bo‘lgan chastota sohalari. Odatda chastota buzilishlarining ruxsat etilgan koeffisient kattaligi 3 dB dan oshmaydi.
- kattaligi kuchaytirgichning o‘tkazish polosasi deyiladi.
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- rasm. Vodorod atomi dipolining tashqi elektrostatik maydonda deformatsiyasi

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- rasm. Vodorod atomi dipolining tashqi elektrostatik maydonda deformatsiyasi
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bet | 8/14 | Sana | 14.05.2024 | Hajmi | 387,21 Kb. | | #230570 |
Bog'liq Fizika fanidan ma\'ruza-44 - rasm. Vodorod atomi dipolining tashqi elektrostatik maydonda deformatsiyasi
va (6.32)
munosabatlarga ega bo‘lamiz.
Demak, induksiyalangan dipolning yelkasi quyidagiga teng bo‘ladi:
(6.33)
va shu dipolning elektr momenti quyidagicha ifodalash mumkin:
(6.34)
Agar (9.1) – ifodadagi ni (9.4) – ifodaga qo‘yilsa, dipolning elektr momenti quyidagi ko‘rinishni oladi:
,
yoki
(6.35)
Buni vektor ko‘rinishda quyidagicha ifodalash mumkin:
(6.36)
Agar atomning xajmini ga teng deb olsak
ga ega bo‘lamiz.
– proporsionallik koeffitsiyenti bo‘lib, unga atomning qutblanuvchanligi deyiladi.
(6.37)
Demak, atomning qutblanuvchanligi uning uchlangan hajmiga teng bo‘lgan fizik kattalikdir.
Endi faraz qilaylik, bir jinsli ( ) tashqi elektrostatik maydonga dielektrikning qutbli molekulasi joylashtirilgan bo‘lsin (5 - rasm). Qutbli dipolning elektr momentining vektori tashqi maydon kuchlanganligi vektori bilan burchak hosil qilsin.
Dipolga quyidagi
va (6.38)
5 - rasm. Tashqi elektrostatik maydonda dipolga ta’sir etuvchi kuchlar
juft kuchlar ta’sir qiladi. Bu juft kuchlarning momenti ning son qiymati quyidagiga teng bo‘ladi
(6.39)
vektor ko‘rinishda esa
(6.40)
bilan ifodalanadi.
vektor va vektorlar yotgan tekislikka perpendikulyar bo‘lib, soat milining yo‘nalishi bilan mos tushadi.
Juft kuchlar momenti , dipolning elektr momenti tashqi elektrostatik maydon kuchlanganligining vektori bilan mos tushguncha ta’sir qiladi.
Dipolning elektrostatik maydon bo‘ylab burilishi dipolli qutblanish yoki oriyentatsiyaviy qutblanish deb ataladi.
Agar dipol bir jinsli bo‘lmagan elektrostatik maydonga kiritilsa, +q zaryad atrofida , -q zaryad atrofida maydon kuchlanganliklari ta’sir qiladi.
Juft kuchlar yig‘indisi quyidagiga teng bo‘ladi.
(6.41)
dipolning yelkasi l bo‘yicha, o‘rtacha maydon kuchlanganligidir, ya’ni
(6.42)
demak,
(6.43)
Skalyar ko‘rinishda esa,
ga tengdir. (9.13) – ifodani quyidagicha ifodalashimiz mumkin
(6.44)
Dielektrikning qutblanganlik darajasini xarakterlash uchun, qutblanish vektori deb ataluvchi fizik kattalik tushunchasi kiritiladi.
Qutblanish vektori deb, dielektrikning bir birlik hajmidagi barcha dipollar elektr momentlarining vektor yig‘indisiga miqdor jihatdan teng bo‘lgan fizik kattalikka aytiladi, ya’ni V elementar hajmdagi n ta dipolning elektr momentlari yig‘indisini V hajmga bo‘lgan nisbatiga teng
(6.45)
bunda – qutblangan i - molekulaning elektr momenti.
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Elektr mаydon energiyasi - Elektrostatika. Elektr toki

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Elektrostatika. Elektr toki
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bet | 6/14 | Sana | 14.05.2024 | Hajmi | 387,21 Kb. | | #230570 |
Bog'liq Fizika fanidan ma\'ruza-4Elektr mаydon energiyasi
Kondensаtor energiyasini uning qoplаmаlаri orаsidаgi elektr mаydonni xаrаkterlovchi kаttаliklаr orqаli ifodаlаylik
bundаgi u/d=e - qoplаmаlаr orаsidаgi mаydon kuchlаngаnligi vа sd=v - qoplаmаlаr orаsidаgi fаzoning hаjmi ekаnini inobаtgа olsаk
Ushbu energiya kondensаtor qoplаmаlаri orаsidаgi fаzodа bir tekis tаqsimlаngаn bo‘lаdi. Fаzoning birlik hаjmigа to‘g‘ri kelgаn ulushini energiyaning zichligi deyilаdi:
Elektr maydonida dielektriklar va o‘tkazgichlar.
Elektronli va dipolli qutblanishlar. qutblanish vektori. Dielektriklar atom va molekulalardan tashkil topgan. Atom esa, musbat zaryadli yadro va manfiy zaryadli elektronlardan iboratdir. Atomning musbat zaryadi yadroda to‘plangan bo‘lib, manfiy ishorali elektronlar esa, yadro atrofida harakatda bo‘ladi.
Ko‘p hollarda manfiy zaryadlarning markazi musbat zaryadli yadro markazi bilan ustma ust tushadi.
Birinchi turdagi dielektriklar (N2, H2, O2, CO2 va b.) molekulalaridagi elektronlar yadro atrofida simmetrik joylashib tashqi elektrostatik maydon bo‘lmaganda, musbat va manfiy zaryadlarning og‘irlik markazlari ustma-ust tushgan bo‘ladi. Bunday dielektriklar molekulalari qutbsiz molekulalar deyiladi.
Tashqi elektrostatik maydon ta’sirida qutbsiz molekula zaryadlari siljiy boshlaydi. Musbat zaryadlar maydon yo‘nalishda, manfiy zaryadlar maydonga teskari yo‘nalishda siljiydi (1 - rasm). Shunday qilib, molekula dipol momentiga ega bo‘ladi.
1 - rasm. Tashqi elektrostatik maydon ta’sirida qutbsiz molekulaning dipol momentiga ega bo‘lishi
Ikkinchi turdagi dielektriklar (H2O, NH3, SO2, CO,…..) molekulalaridagi elektronlar yadro atrofida nosimmetrik joylashgan bo‘ladi va tashqi elektrostatik maydon bo‘lmaganda ham musbat va manfiy zaryadlarning og‘irlik markazlari ustma-ust tushmaydi.
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