Class 8 Science Chapter 4 Combustion And Flame Important Notes

Class- VIII 

Sub- Science

Chapter- Combustion and Flame

Combustion

•       A chemical process in which a substance reacts with oxygen to give off heat is called combustion.

•       Combustion is a process in which a substance react with oxygen to give off heat and light (Not necessary for all condition).

•       The substance that undergoes combustion is called as combustible or fuel.

 

Ignition Temperature “The lowest temperature at which substance catches fire”

 

•       A combustible substance cannot catch fire or burn until its temperature is lower than its ignition temperature.

•       Inflammable Substance “The substance which have low     ignition Temperature and can easily catch fire with a flame” Ex:- LPG, Petrol,   Alcohol etc.

 

HOW CAN WE CONTROL FIRE

 

•       The most common fire extinguisher is water. But water works only when things like wood, paper, clothes, etc.

•       If electrical equipment is on fire, water may conduct electricity and harm those who is trying to control fire with the help of water.

•       Water is also not suitable for fires involving oil and petrol.

•       Water is heavier than oil, so it sinks below the oil and oil keeps burning on the top.

•       To control fires involving electrical equipment and inflammable materials (petrol, oil) carbon dioxide (CO2) is the best extinguisher.

•       CO2 is heavier than oxygen, it covers the fire like a blanket, since the contact between the fuel and oxygen is cut off, the fire gets controlled.

•       Also, CO2  mostly does not harm electrical equipment.

Note:- CO2 is carbon dioxide due to error it is not arranged properly.

 

Types of Combustion

 

    There are two types of combustion

       1)Rapid Combustion

2)    Spontaneous Combustion

•       The gas burns rapidly and produces heat and light, such combustion is called as Rapid Combustion.

•       A combustion in which a material suddenly bursts into flames, without the application of any apparent ( means catch fire themselves due to natural heating) cause is called Spontaneous Combustion.

Flames    

•       A flame is the visible gaseous part of a fire.

•       An area of bright burning gas that comes from something that is on fire.

•       Fire is a rapid oxidation of material.

 

Structure of Flames

    A candle flame is consist of three zones

         1)  Outer zone   (Non luminous Zone)

     2)   Middle Zone   (Luminous Zone)

         3)  Inner Most Zone / Dark Zone  (Least combustion)

Fuel

•       Fuels are those substances which produce heat and light energy on burning. Ex- wood, petrol, coal, LPG etc.

•       Ideal Fuel:-  Ideal fuel is basically cheap combustible and it produces a high among of heat energy. Ex- Natural Gas, LPG

Fuel Efficiency

 

•       The amount of energy released per unit mass of the fuel is called fuel efficiency.

•       The amount of heat energy produced on complete combustion of 1kg fuel is called calorific value.

•       The Calorific Value of a fuel is expressed in a unit is called Kilojoule per KG (KJ/KG).

 

FUEL   Cow dung cake Wood Coal Petrol Kerosene  LPG Hydrogen

KJ/KG (Calorific Value)   6000 – 8000 17000 – 22000 25000 – 33000 45000 45000 55000 150000

 

Harmful Effects on Environment of fuel consumption

 

•       Burning of coal and diesel releases Sulphur Dioxide gas, which is one of the reason of Acid rain.

•       Most of fuel combustion releases Carbon Dioxide, which causes of Global Warming.

•       Incomplete combustion of these fuels gives Carbon Monoxide gas. It is a very poisonous gas.

Thanks for reading this post.

Contemporary India And Education Most Important Questions

Contemporary India And Education

Hello Aspirants,

Welcome to my post,

In this post I'll show you few most Important questions for Contemporary India and Education

I hope you'll like it.

These are few important questions for 4 marks, which is necessary to attempt In B.ed Examination.

Q.1) Objectives of NCF (2005)

Q.2) Problems of Minorities

Q.3) Impact of Education on culture

Q.4) Elementery Education

Q.5) Difference between fundamental right and duties.

Q.6) Democracy and Education

Q.7) How does Education Influence Culture?

Q.8) Three language formula

Q9) Needs of NCF


UNIT - 1 Important questions.

Q1) Examine about Socially disadvantage segment.

Q2) Discuss Directive principal of state police of Indias education.

Q3) Who are marginalized groups ?

Q4) Explain the right to free and compulsory education

Unit - 2 Important questions.

Q1) Discuss main feature of National education policy 1986.

Q2) Discuss main feature of National education policy 1992.

Q3) What is Program of action. How many segment it has ? Discribe

Q4) Bring Out the recommendation of indian education commission (1962-64) regarding guidence and counseling, teacher education and evaluation system.

Unit - 3 Important questions.

Q1) What are the problems generally focused on vocationalisation of education ?

Q2) What is universalization of elementary education ? Explain in detail.

Q3) What do you mean by L.P.G explain in detail?

Q4) What do you mean by Vocationalisation of education? Explain

Unit - 4 Important questions.

Q1) Explain Various "New Economic Reform in India" and their impact on education.

Q2) Critically Examine about " Reservation as an Egalitarian Policy. "

Q3) What changes would like to suggest in present system education for making our democracy a success ?

Q4) What do you understand by integration between Education and Technology?

These were the few most Important questions for B.ed 1st year exam, I hope you like it.

Pedagogy Of Physical Science Important Questions For B.ed 1st Year Exam 2023

Most Important Question For B.ed 1st Year Pedagogy Of Physical Science

Hello Friends,
Welcome to my post,

In this post I'll show you the most Important question of pedagogy of physical science.

Questions for 4 Marks which is compulsory to attempt in every B.ed. exams.

Q1) History of physical science.

Q2) Importance of physical science.

Q3) Responsibility of physical science.

Q4) Science Exhibition.

Q5) Science Trip.

Q6) Difference between Content Analysis and Pedagogy analysis.

Q7) Remedial Teaching.

Q8) Use of Achievement Test.

Above questions are most probably asked in 4 marks questions so prepare it.

Now if you talk about 16 marks questions

These are the following questions.

Unit 1 Important questions

Q1) Write the meaning nature and scope of physical science in school curriculum at secondary level. Also discuss its branches.

Q2) Define Bloom's Texonomy of instructional objectives with suitable examples.

Q3) Difference between aims and objectives. What are the main objectives of teaching physical science.

Unit 2 Important questions.

Q1) Describe Lecture Cum Demonstration method for teaching physical science ? Discuss its merit and demerits.

Q2) Explain the "Skill of questioning". Prepare a mirco lesson plan on this skill on any concept of physical science.

Unit 3 Important questions.

Q1) Discuss the meaning, principal and steps of curriculum construction in physical science.

Q2) Discuss different types of audio visual aids that can be used efficiently in teaching physical science.

Q3) What is Pedagogy. Describe the pedagogical analysis of atomic structure.

Unit 4 Important questions.

Q1) Explain measurements, evaluation, grading and Examination ?

Q2) What do you mean by objectives type test ?

Explain the charecteristics and advantages of objective test.

These were the important questions most probably asked in b.ed 1st year exams of pedagogy of physical science, I hope you like it

and thanks for reading my post.

How To Apply For Postal Jobs In 2023

How To apply for postal jobs in 2023

To apply for postal jobs in 2023, you just need to follow these given steps.



1. Visit the Official Website: Go to the official website of the postal service "indiapost.gov.in" in your country. For example, in the United States, the official website is usps.com.


2. Explore Job Opportunities: Look for a section on the website that provides information about job openings or career opportunities. This section may be labeled as "Careers," "Jobs," or something similar. Browse through the available positions to find ones that match your interests and qualifications.


3. Review Job Requirements: Read the job descriptions and requirements for the positions you're interested in. Make sure you meet the minimum qualifications, which may include education, experience, and other specific criteria.


4. Prepare Required Documents: Gather the necessary documents for your application. This may include your resume or CV, cover letter, identification documents, educational certificates, and any other supporting documents requested in the job posting.


5. Complete the Application Form: Fill out the online application form provided on the website. Be thorough and accurate when providing your personal information, work history, and educational background. Double-check your application for any errors before submitting it.


6. Submit Application: Once you have completed the application form, submit it through the designated online submission system. Some postal services may also accept applications by mail or in person, so follow the instructions provided on the website.


7. Take Required Tests: Depending on the position you're applying for, you may be required to take certain tests, such as a written exam or a pre-employment assessment. Follow the instructions provided by the postal service regarding these tests and prepare accordingly.


8. Attend Interviews: If your application is shortlisted, you may be invited for an interview. Prepare for the interview by researching common interview questions and practicing your responses. Dress professionally and make a positive impression during the interview.


9. Complete Background Check: Postal services often conduct background checks on selected candidates before making a final offer of employment. Be prepared to provide any necessary information or documentation for the background check process.


10. Await Job Offer: After completing the necessary steps, await a decision from the postal service. If you are selected for the position, you will receive a job offer detailing the terms and conditions of employment. Review the offer carefully and respond within the given timeframe.



I hope you are happy with these given steps, with the help of these steps you can apply for postal jobs in 2023.

CUET Result 2023 Is Declared, How To Check Your CUET Result

CUET Result 2023 Is Declared, How To Check Your Result Here

Hello Friends,

In This Blog I'll show it how can you check your result of CUET 2023,

CUET Result 2023 In CUET UG 2023, 82 thousand 207 students of Bihar have achieved success. And more than 275 students of the state have scored 100 percentile.

Apart from this, the students of Bihar have passed the most in English. NTA officials told that the youth of Bihar have preferred Delhi University the most.

CUET has become the second biggest exam of the country. Earlier, about 20 lakh students had participated in NEET, the entrance test for medical. And more than 11 lakh students appeared in CUET. 

Its results have been declared on Saturday. Many new trends have emerged in this. Compared to the number of toppers in CUET in 2022, there has been a significant increase in the number of toppers in the results of 2023.

The criteria for admission to universities at the graduation level is one language plus three best scores. According to this, Hindi or English is taken as one of the languages, after that there are three elective subjects of science, there are three elective subjects of commerce. If we look at the best result, 22,836 students have scored 100 percentile in different subjects. While last year this number was 21,159. This means those with 100 percentile in different subjects are big. Take English only.

Take English only, this time more than 5000 students have scored 100 percentile in English. After that number comes in biology. Around 4850 students have scored 100 percentile in Biology. In Economics, 2836 students have scored 100 percentile. In Political Science, 1796 students have scored 100 percentile. So when we choose Political Science Honors in Arts subjects, then subjects like English, Political Science, History will be included in it, then surely the race for admission will be tough.


To check the result of CUET

ntaresults.nic.in


Thanks for Reading this blog.

केवल 999 रूपये में Jio Bharat V2 Phone लॉन्च किया है जानिये कैसे मिलेगा

 Jio ने केवल 999 रुपये में Jio भारत V2 Phone लॉन्च किया है

Jio Bharat V2 Phone 

सबसे कम कीमत में मिलेगा Jio Bharat V2 Phone

Jio Bharat V2: Recharge plan से भी कम कीमत में Jio ने लॉन्च किया सबसे सस्ता 4G Phone,

Jio Bharat V2 Feature, 

Market में उपलब्ध इंटरनेट पर काम करने वाले जितने भी phone उपलब्ध हैं

उनमें ‘Jio Bharat V2’ का दाम सबसे कम है।

Market में उपलब्ध Internet पर काम करने वाले जितने भी फोन उपलब्ध हैं उनमें ‘जियो भारत V2’ का दाम सबसे कम है। 

999 रु के दाम पर उपलब्ध ‘जियो भारत V2’ का मासिक प्लान भी सबसे बहुत सस्ता है। 

ग्राहकों को 28 दिन की वैलिडिटी वाले प्लान के लिए 123 रु चुकाने होंगे। 

जबकि अन्य ऑपरेटर्स के Voice Call और 2 GB वाले Monthly Plans की शुरुआत ही 179 रु से होती है।

इसके अलावा ‘Jio Bharat V2’ के ग्राहकों को कंपनी 14 GB 4G Data देगी मतलब 0.5 GB data daily मिलेगा इस्तेमाल करने को ।

‘Jio Bharat V2’ पर वार्षिक प्लान भी है जिसके लिए ग्राहक को 1234 रु चुकाने होंगे।

Jio Bharat भी Launch हुआ है 

Company ने 25 करोड़ 2G ग्राहकों को 4G में लाने के लिए 

‘Jio Bharat’ प्लेटफॉर्म भी लॉन्च किया है।

 इस प्लेटफॉर्म का इस्तेमाल दूसरी कंपनियां भी 4जी फोन बनाने के लिए कर सकेंगी। कॉर्बन ने इसका उपयोग शुरु भी कर दिया है। 

विशेषज्ञ उम्मीद जता रहे हैं कि 2जी फीचर फोन की जगह जल्द ही 4जी भारत सीरीज के मोबाइल ले लेंगे।

2जी ग्राहकों को रिझाने के लिए कंपनी 2018 में भी जियोफोन लेकर आई थी। Jio Phone आज लगभग 13 करोड़ से अधिक ग्राहकों की पसंद बना हुआ है।

‘Jio Bharat V2’ से भी कंपनी को यही उम्मीदें हैं। Company ने 7 जुलाई से ‘Jio Bharat V2’ का बीटा Trail शुरु करने की घोषणा की है। 

2G Free India बनाने की कोशिश करते रहे हैं Mukesh Ambani

जियो भारत प्लेटफॉर्म' का उपयोग

123 रु का है मासिक प्लान, 14 जीबी डेटा मिलेगा

Jio Bharat V2 की स्पेसिफिकेशन

देश में निर्मित और मात्र 80 grams वजनी ‘Jio Bharat V2’ 4G पर काम करता है, इसमें HD Voice Calling, FM Radio, 

128 जीबी का SD Memory Card Support करता हैं। मोबाइल में 4.5cm. की TFT screen, 0.3 Megapixel का Camera, 

1000 mAh की Battery, 3.5 mm का Headphone Jack, पावरफुल लाउडस्पीकर और टार्च मिलती है।

भारत की कोई भी प्रमुख भाषा बोलने वाला ग्राहक ‘जियो भारत V2’ में आपकी भाषा में काम कर सकेगा। 

यह मोबाइल 20 से भी अधिक भारतीय भाषाओं में काम कर सकता है।

‘जियो भारत V2’ मोबाइल के ग्राहकों को Jio Cinema के Subscription के साथ Jio-Savan के 8 carore songs का playlist भी मिलेगा। 

ग्राहक Jio-Pay के जरिए UPI पर लेनदेन भी कर सकेंगे। 

For More Details Please Follow Us 

Government Jobs For 12th Pass Students

Government Jobs For 12th Pass Students 

Welcome Guys,

I have some government jobs information for class 12th passed out aspirants.

Here are some common government job options for 12th pass candidates:

1. Clerk: Various government departments and organizations recruit clerks for administrative work. This can include data entry, record maintenance, and other office tasks.

2. Stenographer: Stenographers are responsible for transcribing speeches, dictations, and other spoken words into written form. They are employed in government offices, courts, and other institutions.

3. Postal Assistant: The Indian Postal Service often conducts recruitment drives for the position of Postal Assistant. Responsibilities include sorting and delivering mail, managing accounts, and customer service.

4. Lower Division Clerk (LDC): Many government departments hire LDCs to handle clerical tasks like maintaining records, filing, and assisting with administrative work.

5. Police Constable: State Police Departments frequently recruit candidates for the position of Police Constable. Candidates must meet specific physical and educational requirements and pass a selection process that includes written exams, physical tests, and interviews.

6. Railway Recruitment: The Indian Railways regularly conducts recruitment drives for various posts, such as railway clerks, ticket collectors, and constables. These positions are open to candidates who have completed their 12th standard.

7. Indian Army Soldier: The Indian Army recruits candidates for various positions like Soldier General Duty, Soldier Technical, Soldier Clerk, and others. They conduct recruitment rallies and selection tests across different regions.

8. Indian Navy: The Indian Navy offers opportunities for 12th pass candidates through positions like Sailor, Artificer Apprentice, and Senior Secondary Recruits. Candidates must undergo written exams, physical tests, and medical examinations.

9. Staff Selection Commission (SSC) Exams: The Staff Selection Commission conducts various exams like Combined Higher Secondary Level (CHSL) for the recruitment of candidates in government offices.

10. State Public Service Commission Exams: State Public Service Commissions conduct exams for various positions like Clerk, Assistant, and other administrative roles in state government departments.

These are just a few examples of government job options available for 12th pass candidates.

I hope you guys have liked it

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