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define vaccination. sate the basic principal of vaccination

Posted by Pratap Singh 7 years, 4 months ago

1 answers

Yogita Ingle 7 years, 4 months ago

Vaccination is based on the principle that our body learns to fight against a certain microbe when the microbe attacks our body for the first time. Vaccines are made from dead or weak strains of a microbe. Vaccine is inoculated in the body in appropriate dose. After vaccination, the body learns to fight with that microbe. As a result, our body easily wards off any future onslaught of that microbe. Many diseases can be prevented by vaccines.

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What is meant by hierarchy

Posted by Lalit Gupta 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Riya Sharma 7 years, 4 months ago

a system or organization that has many levels from the lowest to the highest

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What is the difference between fission and fussion.

Posted by Sachin Sachin 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Tanay Falor 7 years, 4 months ago

Fission means to divide Fusion means to conbine

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Earth attract apple. Why does apple do not attract earth?

Posted by Sambhav . 7 years, 4 months ago

CBSE > Class 09 > Science

4 answers

Tanay Falor 7 years, 4 months ago

If the weight of apple will be greater that of earth then apple will attract the earth

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Abhay Upadhyay 7 years, 4 months ago

A/q rule : third law of motion The mass of earth is accupies by force is gravitational force & gravitational force attract all universal thing and also we can say the mass of apple is less than mass of gravitational so apple mass is less & earth mass is more so apple donot exert earth & earth exert apple : the force of apple & earth is pulling same force but is mass is not same.....

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Manit Saharan 7 years, 4 months ago

The mass of earth is greater than the mass of the apple

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Riya Dutt 7 years, 4 months ago

Cause earth have greater mass than the apple

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what is ment by organic farming

Posted by Pratap Singh 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Manit Saharan 7 years, 4 months ago

The farming in which no chemicals are use like pesticides etc are called organic farming

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WHat is the full form of AIDS and HIV?

Posted by Payal Dhiman 7 years, 4 months ago

CBSE > Class 09 > Science

2 answers

Manit Saharan 7 years, 4 months ago

Human immuno deficiency virus

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Animesh Kumar 7 years, 4 months ago

AIDS:- Acquired Immuno Deficiency Syndrome HIV:- Human Immunodeficiency Syndrome

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What are biochemical pathways

Posted by Shalini Vairamani 7 years, 4 months ago

CBSE > Class 09 > Science

0 answers

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Will the mass or charge on the electron change if the potential difference in the discharge tube is increased

Posted by Abida Fathima 7 years, 4 months ago

CBSE > Class 09 > Science

0 answers

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Calculate the work required to be done to stop a moving bus with force 2500 Newton after 3 hours if the speed of the bus is 72km/h

Posted by Vineshrai Rai 7 years, 4 months ago

CBSE > Class 09 > Science

0 answers

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What is molar mass???

Posted by Vivan Aggarwal 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Nishant Singh 7 years, 4 months ago

Molar mass is a physical property defined as the mass of a given substance divided by the amount of substance. It's SI Unit is kg/mol.

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Calculate the number of moles of iron in a sample containing 100000000000000000000000 atoms of iron.

Posted by Laksh Goduka 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

अजेयता डागर 7 years, 4 months ago

Moles=6.022×10^23×10^24 =6.022×10^47 Answerrr

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Rathod has discovered which theory

Posted by Krishna Pandey 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

अजेयता डागर 7 years, 4 months ago

RATHOD IS THE NAME OF SCIENTIST RUTHERFORD........AND RATHOD HAS DISCOVERED THE THEORY THAT HOW ELECTRONS ARE ARRANGED IN THE ATOM.... ANSWER

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How many moles of nitrogen molecular weighs 28g calculate the mass of one molecules of nitrogen in grams

Posted by Raju Patel 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Tanay Falor 7 years, 4 months ago

One mole of nitrogen molecule weigh 28g Mass of one molecule of nitrogen is 28g

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calculate the gravitational force between two objects of masses 10kg and 20 kg at separation of 5m

Posted by Debi Prasad Panda 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

अजेयता डागर 7 years, 4 months ago

M1 =10kg M2=20kg Distance=5m=0.5km Therefore using F=GM1*M2/D^2 F=6.67*10^-11×10×20/0.5M^2 =6.67×10^-11×200/0.25 =6.67×10^-7×2/25 =54×10^-8NEWTON.... ANSWER

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Plama membrane is a selectively parmeable membrane .state

Posted by Sunil Pohankar 7 years, 4 months ago

CBSE > Class 09 > Science

2 answers

Nishant Singh 7 years, 4 months ago

Because it allows entry only of some selected materials and also exit of some certain materials.

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Sachin Yadav 5 years, 11 months ago

Because entri some matrial and exit some material

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An electric iron of 1200watt is used for 30minute every day.Find the electric energy consume in the month of April?

Posted by Aayush Kamal 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

अजेयता डागर 7 years, 4 months ago

Power of iron=1200watt×10000 =1.2 kw Time used=30minutes=0.5hrs... =0.5×30 =15 hrs Power =1.2×15 =18 kwh...... ANSWER

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What is buyoent?

Posted by Neha Panwar 7 years, 4 months ago

CBSE > Class 09 > Science

2 answers

Abhay Upadhyay 7 years, 4 months ago

When the force is acting on upward direction like a ball in a water is up to upward direction is called buyoent force.

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Aayush Kamal 7 years, 4 months ago

The upward force is called buyoent

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Why there are 5 kingdom of living things not (-) or (+) than 5

Posted by Daanish Algur 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Anashuman Singh 7 years, 4 months ago

Yes, monera, protista, fungi, plantae and animalia

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Extra questions ch 1

Posted by Om Kumar 7 years, 4 months ago

CBSE > Class 09 > Science

0 answers

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Why only 5 kingdom not 6

Posted by Afroze Shariff 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

अजेयता डागर 7 years, 4 months ago

BECAUSE THE SCIENTIST HAVE DISCOVERED GIVE KINGDOM...

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If an ice cube containing lead in it is floating on water in a beaker and ice melts, lead sinks to bottom so will the level of water in beaker raise , falls or remains same? Explain.

Posted by Pallavi Lohan 7 years, 4 months ago

CBSE > Class 09 > Science

0 answers

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What ia the structure of atom??????

Posted by Shweta Kumari 7 years, 4 months ago

CBSE > Class 09 > Science

2 answers

अजेयता डागर 7 years, 4 months ago

Structure of atom is a positevely charged sphere in which electrons are embedded......its structure is like watermelon......red part of water melon is positively charged and the seeds of it are the electrons which are embedded in it....ANSWER

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Abhishek Dawer 7 years, 4 months ago

Structure of atom is like sphere and watermelon

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What would happen if hypothetically bose-einstein or fermionic condensate came in contact with quark-gluon plasma ?

Posted by A Z 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

A Z 7 years, 4 months ago

Ux8td

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Eye lence

Posted by Md. Zaffar Salmani 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Biswajit Mandal 7 years, 4 months ago

The power of lence is know as eye lence.

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What is fertilizer

Posted by Biswajit Mandal 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 4 months ago

Fertilizers refer to the products produced commercially to replenish the soil with essential nutrients. The fertilizers enrich the soil with nitrogen,phosphorus and potassium and ensure proper vegetative growth of healthy But continuous use of fertilizers can destroy the fertility of soil as it harms the beneficial micro-organisms in the soil.

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What is our eye lence

Posted by Md. Zaffar Salmani 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 4 months ago

Eye Lens: Behind the pupil, there is a transparent structure called a lens. By the action of ciliary muscles, it changes its shape to focus light on the retina. It becomes thinner to focus distant objects and becomes thicker to focus nearby objects.

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What is time period and what is the relation between time period and frequency

Posted by Simran Sarao 7 years, 4 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 4 months ago

The time period of oscillation of a wave is defined as the time taken by any element of the string to complete one such oscillation.
As we know the distance travelled by a wave is nothing but its wave length l (in case of producing one wave), the time taken to produce a wave its time period (t).
Speed of the wave is the distance travelled the wave due to the production of one wave.
Speed of a wave (v) = Distance (l) / Time (t)
v = l /t

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Give the name and calculate the molar mass of componds given below (1)Al2(So4)3

Posted by Diksha Yadav 7 years, 4 months ago

CBSE > Class 09 > Science