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write about intercropping and mixed cropping

Posted by Rampati Mahto 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

Mixed Farming refers to a cropping system where two or more crops are cultivated in the same piece of land simultaneously. This technique is practised to reduce the risk of total crop failure because of less rainfall or adverse climatic conditions.
Intercropping is a cropping technique in which two or more crops are cultivated simultaneously in the same piece of land adhering to a specific row pattern in order to increase the productivity of the crops. This technique is generally followed by small farmers who are completely dependent on the rainfall for better yield and do not have any other options like canals and tube wells, etc.

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A motor boat starting from the rest of a lake accelerates in the straight line at a constant rate of 3 metre per second square for 8 second how far does the boat travel during this time

Posted by Vineet Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Dheeraj Singh 7 years, 2 months ago

given u=0 a=3m per sec t=8sec using 2nd equation of motion s=ut+1/2(at)2 s= 0×8+1/2 × 3×8×8 s=0+3×4×8 = 96

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Function of plasma membrane - chromosome and ribosome.

Posted by Rampati Mahto 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

Plasma Membrane: Helps in separation of inner and external environment of the cell.It is a selectively permeable membrane and only allows selected material to come inside the cell.
Chromosome: They contain genes which helps in transfer of character of inheritance from parents to the child.
Ribosome: Help in synthesis of proteins. Found in Rough endoplasmic reticulum.

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Can a body have acceleration without change in magnitude of velocity ?explain with an example

Posted by Vineet Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

A body is said to be accelerated if its velocity changes.Velocity comprises of both magnitude and direction.
So yes, a body can have acceleration even if it has constant magnitude.In this case the direction of motion may change.Ex circular motion ,the direction continuously changes.It is accelerated motion even if the speed is constant.

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Differentiate acceleration from the velocity

Posted by Vineet Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

Velocity	Acceleration
Velocity implies the speed of an object, in the given direction.	Acceleration alludes to any change in the velocity of the object with respect to time.
Rate of change of displacement.	Rate of change of velocity.
velocity = Displacement/time	Acceleration + Velocity/time
Unit of measurement is m/s	Unit of measurement is m/s²

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Why female Anopheles Mosquito feed on human blood?

Posted by Vineet Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 2 months ago

The female Anopheles mosquito usually require a blood meal for the development of eggs. After obtaining a full blood meal, the female will rest for a few days while the blood is digested and eggs are developed.

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Harshika Agrawal 7 years, 2 months ago

Because it needs the nutrition for its eggs which isnt in plant juices

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In a slum area many people are suffering from Malaria mention any two unhygienic condition that must be privileging in that locality?

Posted by Vineet Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

In a slum area many people are suffering from malaria mention any two unhygienic conditions that must be prevailing in that locality?
(i) The stagnant water in ponds, wells, ditches, coolers, etc.
(ii) Sustenance of garbage in nearby areas.

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Give the names of abiotic components necessary for life the earth, explain the layers formed by them

Posted by Het Shah 7 years, 2 months ago

CBSE > Class 09 > Science

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Why aPeople suffering from AIDS cannot fight even very small infection

Posted by Vineet Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

Human immunodeficiency virus (HIV) is a retrovirus which infects human beings causing AIDS. AIDS is a disease in which the immune system of the individual gets affected and immunity is reduced. Lymphocytes present in the blood are destroyed by HIV. This makes the infected individuals more vulnerable to other fatal diseases and infections. Hence, infected person's body is not able to fight even minor infections like cold and minor infections can be fatal in this disease.

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give two role of nucleus in the cell

Posted by Vineet Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 2 months ago

Nucleus is the controlling centre of the cell. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins. The genes within these chromosomes are the cell's nuclear genome. The function of the nucleus is to maintain the integrity of these genes and to control the activities of the cell by regulating gene expression.

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Smile Sharma 7 years, 2 months ago

Brain of the cell Centre of the cell Dirctor of the cell

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Why does chromosome contain DNA in the nucleus?

Posted by Vineet Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

Chromosome is an organized structure of DNA and protein found in the nucleus of cells. It is a single piece of coiled DNA containing many genes. These are considered to be the vehicles of heredity as they carry genes. Genes are small points on the chromosome responsible for one character of an individual.

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Why does nuclear membrane have Porus?

Posted by Vineet Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

The pores present on the nuclear membrane allow transport of water-soluble molecules across the nuclear envelope. RNA and ribosomes move out of the nucleus, whereas carbohydrates, lipids and proteins move into the nucleus.

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The number of electron in the outer most 'L'shell of an atom is 5. A). Write its electronic configuration? B). What is its valency and why

Posted by Vineet Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Why does a block of plastic released under water come to the surface of water?

Posted by Vineet Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 2 months ago

The density of plastic is less than that of water, so the force of buoyancy on plastic block (Vp plaste g) will be greater than the weight of plastic block displaced, i.e., (Vp water g). Hence, the acceleration of plastic block will he in upward direction, and comes up to the surface of water.

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How much sulphur should we take so that no residue will form for So2 gas with 160 g of oxygen?

Posted by Ankit Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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How many hydrogen atoms will be there in 200 litre of ammonia gas taken at STP?

Posted by Ankit Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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20 g Nacl is taken into 250 ml of water then what will be the concentration of solution?

Posted by Ankit Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Aman Ff New Lord 7 years, 2 months ago

Volume of solute=20g Volume of solvent=250ml Volume of solution=20+250 ml =270ml Concentration of solution=20/270×100 =7.407% ans.

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Akanksha Kumari? 7 years, 2 months ago

Concentration of solution = mass of solute/ volume of solution = 20/ 250 = 0.08 %

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Difference between mixed cropping multiple cropping

Posted by Faiz Multani 7 years, 2 months ago

CBSE > Class 09 > Science

1 answers

Meghna Thapar 6 years, 1 month ago

Mixed cropping is the practice of growing two or more crops simultaneously on the same field.

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All formula and important questions for 9th final exams

Posted by Ramandeep Kaur 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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All formula in science book

Posted by Hussan Sraa 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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Drive formula of centripetal acceleration?

Posted by Dilip Kumar 7 years, 2 months ago

CBSE > Class 09 > Science

0 answers

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what is the maximum temperature of mercury

Posted by Sangita???? Ankita 7 years, 2 months ago

CBSE > Class 09 > Science

3 answers

Dilip Kumar 7 years, 2 months ago

Mercury is also planet name and metal name Planet Mercury have temperature at day is 427°C at night - 173°C Metal Mercury change into solid state at - 38°C in liquid at room temperature In gas at 356.73°C

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Gaurav Seth 7 years, 2 months ago

The day side of the planet reaches temperatures of up to 800 degrees Fahrenheit (427 degrees Celsius). In contrast, the chilly night side can get as cold as minus 290 F (minus 180 C). The planet has an average temperature of 332 F (167 C).

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Akanksha Kumari? 7 years, 2 months ago

427°C is the maximum temperature of planet mercury.

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Why plants and animals are made of different types of tissues

Posted by Meenakshi Devi 7 years, 2 months ago

CBSE > Class 09 > Science

2 answers

Satyam Kumar 7 years, 2 months ago

Because they have different characteristics and functions from each other like : 1. Movement 2. Energy level, animal uses more energy as compared to plant 3. Pattern of growth 4. Preparation of food 5. Living cell as animal having more living cell as compared to plant 6. Structural organisation animal having most complex structure organisation as compared to plants

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Akanksha Kumari? 7 years, 2 months ago

Because they have different functions to perform and have different mode of nutrition also.

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which wave is used in ultrasound

Posted by Sangita???? Ankita 7 years, 2 months ago

CBSE > Class 09 > Science