Incorrect URL accessed!!!!

ANSWER

Larjest coal

Posted by Afra Nazarine 4 years, 11 months ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 4 years, 10 months ago

The largest coal reserves are in the United States, Russia, China, Australia, and India. In the United States, coal is mined in 25 states and three major regions. In the Western Coal Region, Wyoming is the top producer—about 40% of the coal mined in the country is extracted in the state. The largest coal mine in the world by reserves is the North Antelope Rochelle coal mine in the Powder River Basin of Wyoming, US.

ANSWER

What is a coal and what is uses of coal Answer please and answer in detail

Posted by Aatman Gor 4 years, 11 months ago

CBSE > Class 08 > Science

3 answers

Rahul Kumar 4 years, 11 months ago

Coal is formed from the wood of treees that were buried in the ground thousands of years ago. Due to underground pressure the coal looks black and hard in nature

Gayatri Yarmunwad 4 years, 11 months ago

Uses of coal :- 1.to cook food. 2. In railway engine to produce steam to run the engine. 3.also used in thermal power plants to produce electricity. 4.also used as fuel in various industries.

4Thank You

Gayatri Yarmunwad 4 years, 11 months ago

Coal is as hard as stone and is black in colour. It is one of the fuel used to cook food. Coal is formed from the dead remains of living organisms . It is known as one of the“ fossil fuels”. It is as well as example of exhaustible natural resources.

4Thank You

ANSWER

Can the process of rusting be Called combustion? Discuss .

Posted by Priya Waje 4 years, 11 months ago

CBSE > Class 08 > Science

3 answers

Madhav Garg 4 years, 11 months ago

Yogita Ingle 4 years, 11 months ago

The process of rusting cannot be called combustion due to the following reasons :

Combustion produces energy in the form of heat. No energy is obtained in a rusting process.
Combustion is a chemical process in which a combustible substance reacts with oxygen to produce heat and light whereas in rusting, a metal reacts with oxygen to produce metallic oxide.
Rusting is a very slow process compared to combustion.
Rusting can take place at room temperature whereas combustion takes place only at a specific ignition temperature.

Adyasha Patra 4 years, 11 months ago

yes

ANSWER

Defination of coal

Posted by Snehal Patil 4 years, 11 months ago

CBSE > Class 08 > Science

3 answers

Anannya Mahato 4 years, 11 months ago

A type of black mineral that is dug(mined) from the ground and burned to give heat.

Aatman Gor 4 years, 11 months ago

Coal is a hard rock which can be burned as a solid fossil fuel. It is mostly carbon but also contains hydrogen, sulphur, oxygen and nitrogen. It is a sedimentary rock formed from peat, by the pressure of rocks laid down later on top.

Yogita Ingle 4 years, 11 months ago

Coal is a fossil fuel, that was formed by the decay of vegetation, which existed millions of years ago. It is a non-crystalline form of carbon. Carbonisation: The slow process of conversion of dead vegetations into coal is called carbonisation.

ANSWER

Difference between Traditional methods of irrigation and Modern methods of irrigation

Posted by Rachana H 4 years, 11 months ago

CBSE > Class 08 > Science

2 answers

Yogita Ingle 4 years, 11 months ago

Traditional methods

1. It takes more time to get the work done

2. More manual work is required

3. Less expensive

4. Water is wasted

Modern methods

1. It takes less time to get the work done.

2. Less manual work is required

3. More expensive

4. Water is conserved by use of better methods of irrigation

Arushi Ranjan 4 years, 11 months ago

In Traditional methods of irrigation it need man power in many activities like pulling the rope but in modern methods it doesn't need man power it isliye supply water through pipe.

ANSWER

Advantage and disadvantages of microorganisms

Posted by Sakshi Padyar 4 years, 11 months ago

CBSE > Class 08 > Science

3 answers

Jasleen Kaur 4 years, 11 months ago

Advantages of microorganisms:- 1). They are used in wine making , baking , and other food making process. 2). Alcoholic fermentation by yeast is widely used in the preparation of wine and bread . A bacterium Lactobacillus , promotes of curd . 3). Yeast reproduces rapidly and produces carbon dioxide during respiration . Bubbles of the gas fill the dough and increases it's volume . 4). Microbes are used to reduce pollution . For example, decomposers such as bacteria and fungi break down dead bodies and excreta to form inorganic compounds , which can be absorbed by plants . 5). They are used to increase the soil fertility by fixing the atmospheric nitrogen with the help of bacterium Rhizombium and some other blue - green algae . 6). Microbes also play an important role in the preparation of medicines . 7). Antibiotics are chemicals produced by micro - organisms to kill bacteria . Streptomycin , for example is an antibiotic. 8). Certain microbes are also used in the biological treatment of sewage and industrial effluents. 9). Antibiotics are used to control many plants diseases. 10). Antibiotics are mixed with the feed of livestock and poultry to check microbes inflection in animals . Disadvantages of microorganisms :- 1). Micro - organisms cause diseases in animals . For ex. in humans , bacteria cause diseases such as tuberculosis , cholera , typhoid . 2). In cattle the foot and mouth disease is caused by a virus . 3). Also , several microbes cause diseases in plants . For example the productivity of wheat , orange , apple , etc. is reduced due to microbial diseases in plants. 4). Certain microbes , entering into our body , produce toxic substances . This leads to food poisoning . Some micro - organisms such as fungus spoil our food . For example , bread when left unused under moist conditions gets spolit by fungus , producing a white - cotton - like growth on the bread .

Meghna Thapar 4 years, 11 months ago

Harmful Microorganisms:

Microorganisms can be harmful in many ways. For example – some of the microorganisms cause diseases in human beings, other animals and plants. Such microorganisms which cause diseases are called pathogens.

Disease causing Microorganisms in Humans:

Pathogens enter our body through the air we breathe, the water we drink or the food we eat. They can also get transmitted by direct contact with an

infected person or carried through an animal. Microbial diseases that can spread from an infected person to a healthy person through air, water, food or physical contact are called communicable diseases. Examples of such diseases include cholera, common cold, chicken pox and tuberculosis.

The communicable diseases can occur and spread in the following ways:

By breathing of air containing microorganisms.
By taking infected food and water.
Through insect bites.
By sharing infected injection needles.
By physical contact with an infected person.For example – common cold disease spreads by breathing air containing microorganisms.

Meghna Thapar 4 years, 11 months ago

The beneficial effects of microorganisms in detail:

Making of Curd and Bread: Lactobacillus bacterium present in milk promotes the formation of curd. It multiplies in milk and converts it into curd. Bacteria are also involved in the making of cheese, pickles and many other food items. Yeast is used in the baking industry for making bread. When yeast is mixed in dough for making bread, the yeast reproduces rapidly and gives out carbon dioxide gas during respiration. The bubbles of the carbon dioxide gas fill the dough and increase its volume. This makes the bread rise and light, soft and spongy.

Commercial Use Of Microorganisms: Microorganisms are used for a large scale production of alcohol and acetic acid. Yeast is used in making alcohol and wine because it is capable of converting sugar into alcohol. The sugar for making alcohol comes from the substances such as cane juice and fruit juices, or from substances like barley, maize, rice, etc. The process of conversion of sugar into alcohol by the action of yeast is called fermentation. Louis Pasteur discovered the process of fermentation in 1857.

Medicinal Use of Microorganisms: A medicine which stops the growth of, or kills the disease-causing microorganisms is called an antibiotic. The source of antibiotic medicines are microorganisms. These days a large number of antibiotics are produced from microorganisms such as fungi and bacteria. Some of the common antibiotics which are made from fungi and bacteria are Penicillin, Streptomycein, Erythromycein and Tetracycline. Antibiotics kill the disease-causing microorganisms but usually do not damage human body cells. The first antibiotic ‘penicillin’ was discovered by Alexander Fleming by chance in 1929, and was extracted from the tiny fungus called ‘Penicillium’. Antibiotics are used to treat many bacterial diseases in humans but are not effective against the diseases caused by viruses. They can be used to treat many diseases in animals. They are mixed with the feed of live stock and poultry birds to control microbial diseases in animals. Antibiotics are also used to control many plant diseases.

Vaccine: Microorganisms are used to make vaccines to provide immunity against a particular disease. A vaccine contains the dead or weakened but alive microorganisms of a disease. When the vaccine is introduced into the body of a healthy person orally or by injection, the body of that person responds by producing some substances called antibodies in the blood. The antibodies remain in the blood of the person for a long time and fight against the same microorganisms and kill them if they happen to enter the body naturally or later date. This is how a vaccine works. Thus, a vaccine develops the immunity from a disease. Several diseases can be prevented by vaccination including cholera, polio, tetanus, measles, rabies, diphtheria, tuberculosis, smallpox and hepatitis. Edward Jenner discovered the vaccine for smallpox in 1798.

v. Increasing Soil Fertility: Some of the microorganisms present in the soil can fix nitrogen gas from the atmosphere to form nitrogen compounds. These nitrogen compounds mix with the soil and increase the fertility of the soil. Example – some bacteria and blue-green algae. Such microbes are commonly called as biological nitrogen fixers.

ANSWER

Applications of Force and Pressure

Posted by Geetanjali Devi 4 years, 11 months ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 4 years, 11 months ago

An applied force is an interaction of one object on another that causes the second object to accelerate or change velocity or direction. The force can be a push, pull, or drag. The resulting direction of an object depends on the relative direction of the force on the object. When air is sucked out of a drinking straw, the air pressure inside if decreases and the atmospheric pressure outside forces the liquid to go inside the straw. ... Skis have a large area to reduce the pressure on the snow.

3Thank You

ANSWER

Why more pressure deep in the sea

Posted by Mohit Silaich 4 years, 11 months ago

CBSE > Class 08 > Science

2 answers

Roshan Mishra 4 years, 11 months ago

Because, ln depth their is a some quantity of magnet (magnetic source )

Yogita Ingle 4 years, 11 months ago

As the depth of the sea increases, the pressure increases since pressure increases with depth. The pressure exerted by water deep under the sea is much greater than at the sea level. Hence, the deep sea divers wear special suits which protect them from extreme pressure of water. These suits are called diving suits. These suits contain buoyancy compensators to combat the weight of their diving equipment and the pressure of water at great depths.

ANSWER

What are synthetic fiber? Name five synthetic fiber .

Posted by Sunil Tamang 4 years, 11 months ago

CBSE > Class 08 > Science

3 answers

Prasad Naik 4 years, 11 months ago

Which are man made ,nylon

Yogita Ingle 4 years, 11 months ago

A Synthetic Fibre is a chain of small units of chemical substances joined together. Many such single units combine to form single unit called Polymer. Polymer means made of many units joined together.

They include nylon, acrylics, polyurethane, and polypropylene.

Nethranandh Vijay 4 years, 11 months ago

Nylon rayon polyester acrylic bakelite

ANSWER

Plz send a Link for the best maths teacher for class 12th

Posted by Richa Mittal 4 years, 11 months ago

CBSE > Class 08 > Science

2 answers

Abdur Rehman 4 years, 11 months ago

Sat poshniya vikas se aap kia samajhte hain

Nethranandh Vijay 4 years, 11 months ago

Bbxbbdbbxbdbbdbxbdbbddbxbbxbxbbxbcbbcbbcbcbcbcbbxbxbxbxbbxbxbbxbxbxbbxnxnxnxnbxbxbxbbxnxnx

ANSWER

Is it a combination rxn or decomposition rxn .......When calcium hydroxide solution reacts with carbon dioxide gas to form calcium carbonate and water....and why

Posted by Richa Mittal 4 years, 11 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

GIVE TWO DIFFERENCE BETWEEN A ZYGOTE AND A FOETUS

Posted by Cyrus Mitra 4 years, 11 months ago

CBSE > Class 08 > Science

1 answers

Rupam Das 4 years, 11 months ago

Zygote and Foetus are the two different terminologies, which refers to the developmental stages inside the mother’s womb or uterus. The zygote is the initial stage in baby development. It is also known as a fertilized ovum formed from the union of the sperm cell and the egg cell. Foetus refers to the final stage in baby development. An embryo is termed as the foetus in the beginning in the 11th week of pregnancy.

ANSWER

what is the meaning of threshing

Posted by Vaishnavi Padshetty ....... 4 years, 11 months ago

CBSE > Class 08 > Science

2 answers

Kt King 4 years, 11 months ago

Threshing means separation of grains from chaff..

Yogita Ingle 4 years, 11 months ago

The process of beating out the grains from the harvested crop plant is called threshing. Threshing is done to take out the grain from its outer covering called chaff.

ANSWER

Why sperm is smaller in size than ovum?

Posted by Soundarya More 4 years, 11 months ago

CBSE > Class 08 > Science

2 answers

Manas Kumar Deka 4 years, 11 months ago

That is the major reason why egg is so much larger. In addition, egg contains almost all organelles, materials, and nutritions for zygote growth. However, asperm only contains haploid chromosome and certain mitochondria for movement. This is the second reason why egg is larger than sperm.

Soundarya More 4 years, 11 months ago

Urgent answer needed till tomorrow

ANSWER

What is. Combution

Posted by Aryan Thakare 4 years, 11 months ago

CBSE > Class 08 > Science

2 answers

Yogita Ingle 4 years, 11 months ago

A chemical process in which a substance reacts with oxygen to give off heat and light is called combustion.
The burning of wood is an example of combustion.

Rakesh Kundrapu 4 years, 11 months ago

Hii

ANSWER

Exam fear. Com use or waste

Posted by Praneash Balasubramaniyan 4 years, 11 months ago

CBSE > Class 08 > Science

1 answers

Aryan Thakare 4 years, 11 months ago

It is helpful

ANSWER

About amoeba

Posted by Praneash Balasubramaniyan 4 years, 11 months ago

CBSE > Class 08 > Science

3 answers

Aryan Thakare 4 years, 11 months ago

Amoeba is a single cell organism Which can seen in microscope

Praneash Balasubramaniyan 4 years, 11 months ago

Amoeba

Praneash Balasubramaniyan 4 years, 11 months ago

About amoeba

ANSWER

What is sexual reproduction explain

Posted by Ashwani Singh 4 years, 11 months ago

CBSE > Class 08 > Science

2 answers

Diksha Singh 4 years, 11 months ago

the mode of reproduction in which two parents are involved to produce a new offspring is called sexual reproduction

Dïvyam Pangaria 4 years, 11 months ago

sexual reproduction is a type of reproduction in which 2 parents are involved

ANSWER

What is green manure ?

Posted by Nikita Srivastava 4 years, 11 months ago

CBSE > Class 08 > Science

2 answers

Ishwara Kumar 4 years, 11 months ago

Jxhdjblf

Yogita Ingle 4 years, 11 months ago

organic matter and nutrients like Nitrogen and Phosphorous to the soil. Commonly used green manure crops: Guar and Sunhemp.

Macronutrients provided by green manure are nitrogen and phosphorus.

ANSWER

What is green manure

Posted by Nikita Srivastava 4 years, 11 months ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 4 years, 11 months ago

Green manuring is the practice of ploughing green plants into the soil for improving the fertility. Green manure provides organic matter and nutrients like Nitrogen and Phosphorous to the soil. Commonly used green manure crops: Guar and Sunhemp.

Macronutrients provided by green manure are nitrogen and phosphorus.

ANSWER

????? ??? ????? ?? ???? ?? ??????? ??????? ????.

Posted by ??????? ???????? 4 years, 11 months ago

CBSE > Class 08 > Science

3 answers

Dïvyam Pangaria 4 years, 11 months ago

iodine

A B 4 years, 11 months ago

Mera lund

Yogita Ingle 4 years, 11 months ago

Non-metal like chlorine (CI₂) is used in water purification process. Non-metal (I₂) is used in the purple coloured solution (Iodine solution) on wounds as antiseptic.