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Why is using excess fertilizers disadvantageous

Posted by Jahanvi Sharma 6 years ago

CBSE > Class 08 > Science

2 answers

Yogita Ingle 6 years ago

1.They get washed away by water easily and cause pollution.
2.They harm the microbes present in soil.
3. They reduce soil fertility.
4.They are expensive.
5.They provide only short term benefits.
6. They change the nature of soil, making it either too acidic or too alkaline.

Divyansh Sharma. 6 years ago

Because it's harmful for the environment and make the soil loose its fertility and soon

ANSWER

Advantages of using CNG

Posted by Kanthi Prakash 6 years ago

CBSE > Class 08 > Science

2 answers

Yogita Ingle 6 years ago

he advantages of using CNG as fuel are as follows:

They both are cleanest burning fuels of all fossil fuels.
They are less polluting, non-corrosive.
They can be sent through pipes easily.
These are easily available and have affordable cost.
LPG and CNG both are easy to store and transport.
As there calorific value is very high therefore, they are used for cooking purpose.

Jahanvi Sharma 6 years ago

1.causes no pollution 2.cheaply available

ANSWER

Larynx and explain it's function

Posted by Raman Prakash 6 years ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 6 years ago

Larynx is a part of the throat. It is responsible for production of sound.
Larynx moves when we swallow something. Inside the larynx, there are two vocal cords. There is a small gap between them. This small gap allows air to pass through. When we speak, air is forced into this small gap by the lungs. This prompts vocal cords to vibrate. Since vibrating objects produce sound, sound is produced due to the vibration of vocal cords.

ANSWER

Why are chloroplast found in plant cells only

Posted by Rashida Saifuddin 6 years ago

CBSE > Class 08 > Science

1 answers

Jahanvi Sharma 6 years ago

Because plants make their food themselves using nonliving things ang humans make food using living things obtained from plants

ANSWER

Why we need to grow the crops

Posted by Angel Arora 6 years ago

CBSE > Class 08 > Science

2 answers

Krishna Chauhan 6 years ago

To obtain food in a large amount for survival we grow crop

Jahanvi Sharma 6 years ago

We get food from crops and if there were no crops ,we would die due to lach of food

ANSWER

Explain how fertiliser are different from manure.

Posted by Mohd Asif 6 years ago

CBSE > Class 08 > Science

3 answers

Angel Arora 6 years ago

Fertiliser are man made organic substance. It is prepared in the factory. It is very rich in nutrients like phosphate sulphate ammonium etc. It does not provide any humus to the soil

Rahul Raj Yadav 6 years ago

FERTILISER-It is a chemical and natural substance. It is prepared in factory. It is rich in nutriants like NPK ( nitrogen phasphorus potassium). It does not provide humas to soil. MANURE- it is a netural substance obtain by the decompasation of plant and animal wastes. It provide humas to the soil. It prepared in field. It is really less rich nutriants.

Yogita Ingle 6 years ago

Fertilizers are chemical in nature and these are manufactured in factories.
Manure is an inorganic substance that is obtained from decomposition of vegetable and animal wastes.

•Microbes are not needed for fertilizers formation.
Microbes are needed to form manure since they degrade the organic substances.

•Fertilizers are easy to transport ,store and apply to crops.
It is difficult to transport ,store and apply manure to crops

.•Fertilizers do not restore soil texture.
Manure restore soil texture.

•Fertilizers do not help in retention of water.
Manure help in the retention of water.

ANSWER

Name common mould?

Posted by Kŕïšhñà Kâñť 6 years ago

CBSE > Class 08 > Science

2 answers

Hermoine Granger 6 years ago

Common Bread Mould : RHIZOPUS

Yogita Ingle 6 years ago

The common moulds are..

1. Aspergillus

2. Acremonuim

3. Alternaria

ANSWER

If we drop out of some water on fabrics,wood,plastics anything then it changes it initial colour to dark color of it?

Posted by Rahul Kumar 6 years ago

CBSE > Class 08 > Science

1 answers

Gurman Kaur 6 years ago

By

ANSWER

Give 2 examples of natural and synthetic fibers

Posted by Ninja Gaming 6 years ago

CBSE > Class 08 > Science

1 answers

Hermoine Granger 6 years ago

Natural : COTTON & SILK Synthetic : POLYESTER & NYLON

ANSWER

A blacksmith hammer a hot piece of iron while making a tool How does the force due to hammering affect the piece of iron

Posted by Pragati Kumar 6 years ago

CBSE > Class 08 > Science

2 answers

Angel Arora 6 years ago

The muscular force can be applied on it and it's shape was changed from iron piece to tool

Hermoine Granger 6 years ago

The muscular force applied by the blacksmith through hammer ⚒ on the hot ♨ iron ⚨ piece changes the shape of the hot iron

ANSWER

Why are the virus are non living ????

Posted by Amogh Raj 6 years ago

CBSE > Class 08 > Science

5 answers

Hermoine Granger 6 years ago

Viruses are a borderline between living and non living.... They can love inactive for thousands of years and reproduce inside a host cell

Hermoine Granger 6 years ago

All the above answers are wrong

Prathamesh Chakrawar 6 years ago

viruses do not make functions like all other organisms as they do not have thier existence in the nature ,but we cant say them non living or also living organism

Ayesha Khatua 6 years ago

Virus are both living and non -living . Without host cell it will die.

Arnav Garg 6 years ago

We can't say Virus are non living as they are living andreplicate and infect our body quickly if inhaled. But the can't do anything outside our body and they are like dead organisms floating in the air.Thus they are said to be on the borderline of living and non living organisms

ANSWER

The name of fungus that can degrade the plastic

Posted by Param Paida 6 years ago

CBSE > Class 08 > Science

2 answers

Ayesha Khatua 6 years ago

Aspergilius Penicillium ,trichoderma are the new reported to degrade PU.

Amogh Raj 6 years ago

Not discovered

ANSWER

What things are necessary to provide food for a large population

Posted by Aashna Malik 6 years ago

CBSE > Class 08 > Science

3 answers

Angel Arora 6 years ago

Proper management and distribution is necessary

Krishna Chauhan 6 years ago

Crop

Amogh Raj 6 years ago

Fertilizer are use to More production

ANSWER

what is ment by pasteurisation

Posted by Dattatrya Raykar 6 years ago

CBSE > Class 08 > Science

5 answers

Ayushi Kapoor 6 years ago

Pasteurisation is when milk is heated at 70° C for about 15-30 seconds and then suddenly cooled.

Prerana Sharma 6 years ago

It is a method of preserving liquid by heating it to a high temperature and then cooling it rapidly ,this prevents the growth of microbes

Ezra Naomi Roy 6 years ago

The milk is heated for 70 degree Celsius for 15 to 30 seconds. By doing so, it will prevent the growth of microbes. This process is called pasteurisation which was discovered by Louise Pasteur in 1882

Yogita Ingle 6 years ago

Pasteurisation is one type of food preservation method. Pasteurisation is the process developed by Louis Pasteur, especially to store milk. In pasteurisation, milk is first heated to about 70 degrees Celsius for 15 to 30 seconds. Then it is suddenly chilled and stored. This prevents the growth of microbes. Pasteurisation deactivates the microbes and reduces the enzyme activity by reduction of temperature.

🖤 🖤 6 years ago

Pasteurization means that milk is boiled at high temperature and then cooled down suddenly, these causes death of harmful microbes present in it. It was discovered by Louis Pasteur.

ANSWER

What is Pascal's law of hydraulic cycle?

Posted by Utkarsh K 6 years ago

CBSE > Class 08 > Science

0 answers

ANSWER

What is farmyard manure??

Posted by Anshuman Ojha 6 years ago

CBSE > Class 08 > Science

1 answers

Divyansh Sharma. 6 years ago

Collected from farm waste

ANSWER

What is metamorphosis in frog and star fish? With example

Posted by Divya Kumari 6 years ago

CBSE > Class 08 > Science

1 answers

Samaksh Aditya 6 years ago

The tapdole swimming in the shallow water changes into a frog or toad.Many other animal undergo change in form apperance during the development from egg to adult for example the creature that emarge from a star fish is much too small to live and feed in the same way as the adult star fish

ANSWER

Write 10 microorganism with define

Posted by Samaksh Aditya 6 years ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 3 months ago

Those organisms which are too small to be seen without a microscope are called microorganisms. Microorganisms are present in soil, water and air around us. They are classified into four major groups – bacteria, fungi, algae and protozoa. Viruses are also microorganisms but they need a specific host for their reproduction. Some of the microorganisms are harmful to us as they cause diseases in human, plants and animals. Diseases like polio and chicken pox are caused by viruses. Diseases like dysentery and malaria are caused by protozoa (protozoans) whereas typhoid and tuberculosis (TB) are caused by bacteria.

ANSWER

Which force is used in the rocket during its launching?

Posted by Nidhi Narang 6 years ago

CBSE > Class 08 > Science

2 answers

Angel Arora 6 years ago

Two forces acting on the rocket during it's launch: 1)Gravitational force 2)Frictional force

Gaurav Seth 6 years ago

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The two forces acting on the rocket are the force of gravity, which pulls the rocket towards the ground, and the force of friction due to earth’s atmosphere, which opposes its motion.<button aria-label="like this post" title="like this post">
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ANSWER

What is Source?

Posted by Bajrang Chaudhary 6 years ago

CBSE > Class 08 > Science

2 answers

Satvik Singh Yadav 6 years ago

A place, person or thing where something comes or starts from or where something is obtained.

Ash Cheema 6 years ago

The place from where we get resources are called sources

ANSWER

Preparation of the soil:

Posted by Madhavi Khadkiwala 6 years ago

CBSE > Class 08 > Science

2 answers

Samaksh Aditya 6 years ago

Adding manure and fertilizer in the soil.

Pawan Prakash 6 years ago

It is the first step befor growin a crop. One of the most important task is to turn the soil and losen it.This allow the root to penetrate deep into the soil. The process of losing and Turing of soil is called tilling or plouging which is done by a ploug. Plougs are made up of wood or iron. The plouged field may have big pieces of soil called crumbs. This crumbs are broken and the field are levelled for sowing and for irrigation.

ANSWER

Difference between flora and fauna

Posted by Shailesh Sanghani 6 years ago

CBSE > Class 08 > Science

4 answers

Sia ? 6 years ago

Flora	Fauna
1.The plants, that are found in a particular area are called flora.	1. The animals, that are found in a particular area are called fauna.
2. It makes its food with help of solar energy.	2. They cannot make their own food so they are dependent upon the flora.
3. It was the very first form of life appeared on the earth in chronological history of the earth.	3. They developed on the earth after the fauna because they are dependent upon the fauna.
4. cannot move.	4. can move.
5.For the example, Sal, teak, jamun etc.	5.For example, Chinkara, cheetal, leopard etc.

Nuthan Nishchay 6 years ago

Flora means plants and fauna means animals

Amitesh Tiwari 6 years ago

If plants are found on particular area then it is flora and if animals then it is fauna

Bellamkonda Surya Kiran 6 years ago

Flora means plants whereas fauna means animals

ANSWER

With what max. acceleration can a firemen slide diwn a rope whose breaking strength is 2/5th of his weight ?

Posted by Sahil Chaurasiya 6 years ago

CBSE > Class 08 > Science

1 answers

Shivam Kriplani 6 years ago

2/5 wieght 5+2 7

ANSWER

What is the defination of friction

Posted by Yash Bhardwaj 6 years ago

CBSE > Class 08 > Science

5 answers

Prerana Sharma 6 years ago

Friction is the force that opposes the motion of a moving object

Bellamkonda Surya Kiran 6 years ago

force of friction always opposes the motion of an object .it tends to stop a moving object. it tends to prevent a stationary object from moving. friction is a contact force. it acts when one surface tries to move over another .interlocking of irregularities of the two surfaces is the cause of friction

Rahul Raj Yadav 6 years ago

The force act on the opposit direction of motion is called friction.????

Yogita Ingle 6 years ago

Friction: When one surface is moving over another surface, a force comes into play and opposes their relative motion. This force is called friction or force of friction. Friction always opposes motion because it acts in opposite direction to motion. Force of friction arises due to contact between two surfaces. If there is no contact between two surfaces there would be no friction.

Arif Khan 6 years ago

Friction is caused by the irregularities on the two surfaces in contact.

ANSWER

How is wildlife important for us?

Posted by Satvik Singh Yadav 6 years ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 6 years ago

Wildlife Conservation is the practice of protecting wild plant and animal species and their habitats. Wildlife plays an important role in balancing the environment and provides stability to different natural processes of nature.
It is important to us
Wildlife Conservation is the practice of protecting wild plant and animal species and their habitats. Wildlife plays an important role in balancing the environment and provides stability to different natural processes of nature.

ANSWER

What is micro organisam

Posted by Prakash Dev 6 years ago

CBSE > Class 08 > Science

7 answers

Bellamkonda Surya Kiran 6 years ago

The organisms that cannot be seen through naked eye are called microorganisms. microorganisms are classified into five types bacteria, virus, algae protozoa, virus.These microorganisms are divided according to number of cells into three types. They are unicellular, multicellular and non cellular. Examples of unicellular organisms are amoeba, Paramecium, bacteria,etc. Examples of multicellular organisms are plants and animals. Examples of non cellular organisms are viruses

Rahul Raj Yadav 6 years ago

Those organisms which cannot seen through the naked eyes and it can be seen through the microscope

Kiran Kumari 6 years ago

The organisms which cannot be seen by our naked eyes are called micro organisms

Ravi Kumar 6 years ago

The organisms that are so small or that can only be through a powerful microscope.

Suhani Singh 6 years ago

Those organism which are not sean by nacked eye are called microorganisms

Isha Prasad 6 years ago

The organisms that cannot be seen through our naked eyes are called microorganisms. Ex: Fungi on bread mould

Akshit Thakur Singh 6 years ago

A small organism which cannot.which cannot be seen by our eyes.

ANSWER

Atomic number of copper is

Posted by Anjali Saijari 6 years ago

CBSE > Class 08 > Science

4 answers

Sia ? 6 years ago

Copper is a chemical element with the symbol Cu (from Latin: cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity.

🖤 🖤 6 years ago

Copper's atomic number is 29. Its chemical composition is Cu

Rahul Raj Yadav 6 years ago

29

Akshit Thakur Singh 6 years ago

Cu

ANSWER

Explain excretory system

Posted by Mamta Jarwal 6 years ago

CBSE > Class 08 > Science

1 answers

Sia ? 6 years ago

The system which is involved in excretion of nitrogeneous wastes from body is called excretory system.

ANSWER

What is atmospheric pressure? What is caused by?

Posted by Khushi Garg 6 years ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 6 years ago

Atmospheric pressure is the force exerted on the each part of the earth's surface by the column of air above the earth.

We simply define what atmospheric pressure is, what causes it and how it's measured.

Atmospheric pressure is the force exerted on the earth's atmosphere on each part of the earth's surface.
Atmospheric pressure is caused by the weight Of air above the earth's surface.
Atmospheric pressure varies with the altitude of the earth's surface.
At high altitudes the pressure is low.
Atmospheric pressure is measured using a barometer.
The units for measuring atmospheric pressure is mmHg.

ANSWER

What is cell wall?

Posted by Dishu Sharma 6 years ago

CBSE > Class 08 > Science

5 answers

Akshit Thakur Singh 6 years ago

Outer surface of cell is called cell membarne.

Rahul Raj Yadav 6 years ago

Cell wall is the outer covering of plant cell it is present in outside of the cell membrane. ??????

Yogita Ingle 6 years ago

The cell wall is the outermost covering of plant cells. It is present outside the cell membrane and is tough, flexible and sometimes rigid in its texture. It is mainly composed of cellulose, long fibres of carbohydrates including hemicellulose, lignin, and pectin.

Khushi Garg 6 years ago

Cell wall is on plant cell. It cover like the cell membrane

Ravi Kumar 6 years ago

Cell wall is surrounded by cytoplasm.

ANSWER

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