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because the rate of evaporation increase with an increase of surface area in the case of saucer as compared to cup and those hot tea or milk in saucer cools faster than a cup so we are able to SIP hot tea or milk faster from a saucer rather than a cup.

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ANSWER

How to find mass number of an element

Posted by Arsh Pathan 7 years, 1 month ago

CBSE > Class 09 > Science

4 answers

Paras Sharma 7 years, 1 month ago

It is the sum of protons and neutrons of the nucleus of an atom.

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Sahil Nandode 7 years, 1 month ago

Mass of carbon is 12u because it has 6 protons and 6 neutrons,6u+6u=12u similarly the mass of aluminium is 27u 13 protons+14neutrons . In short the mass number is the sum of proton and neutrons as the mass of the atom is present at the nucleus

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Pragun Sharma 7 years, 1 month ago

S The sum of number of proton and number of neutron of an element or even an comound

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Akanksha Kumari? 7 years, 1 month ago

Mass no. = no. of protons + no. of neutrons

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ANSWER

What is milting point

Posted by Manav Nigam 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Manav Nigam 7 years, 1 month ago

Thanks for given correct answer

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Arsh Pathan 7 years, 1 month ago

The temperature at which a solid began to start melting that temperature is called the melting point of that solid

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Sahil Nandode 7 years, 1 month ago

Melting point is the temperature when a solid starts melting EG:- ice melting at 0 degree Celsius

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Why does needle have a sharp tip

Posted by Simarjot Kaur 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Pragun Sharma 7 years, 1 month ago

Neddle have sharp tip becaue it have an less surface area so its pressure is high so the needle is more suspend in wall

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ANSWER

diffrence between element and compound

Posted by Sangita???? Ankita 7 years, 1 month ago

CBSE > Class 09 > Science

4 answers

Sangita???? Ankita 7 years, 1 month ago

thanks u all but i need a comparison chart

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Komal Kaur 7 years, 1 month ago

Element first. Cannot be broken down into simpler substance second. For example copper and oxygen and iron. Compounds first. Have fixed composition can be broken down into elements by chemical or electrochemical reactions second. For example water salt and sugar

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Sahil Nandode 7 years, 1 month ago

Compound:-a compound is a substance composed of two or more elements chemically combined with one another in a fixed proportipn . Element:- an element is a basic form of matter that cannot be Brocken down into simpler substance by chemical reactions

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Simarjot Kaur 7 years, 1 month ago

Elements are made from same type of atoms ex mercury,sodium Compounds are made from two or more elements ex boron , carbon

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ANSWER

what is a evapuration

Posted by Sohaib Saifi 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Sahil Nandode 7 years, 1 month ago

The phenomenon of change of liquid into vapours at any temperature below it's boiling point is know as evaporation

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Yogita Ingle 7 years, 1 month ago

The process of a liquid changing into vapour (or gas) even its boiling point is called evaporation.
The wet clothes dry due to evaporation of water present in them. Common salt is also recovered from sea-water by the process of evaporation.

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ANSWER

We feel cool after doing vigorous exercise. Why

Posted by Vinayak Madivalappa 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Diya Tahiliyani 7 years, 1 month ago

It is so because ,when we exercise,there is sweat on our body and when this sweat evaporates, it takes LHV from our body, so our body feels cool

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ANSWER

Give relation between g and G

Posted by Aditi Singh 7 years, 1 month ago

CBSE > Class 09 > Science

4 answers

Simarjot Kaur 7 years, 1 month ago

g=9.8m/s^2 and G=6.67×10^-11Nm^2/kg^2

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Shubham Pandey 7 years, 1 month ago

g=10.m/s^2 or 9.8 m/s^2

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Shubham Pandey 7 years, 1 month ago

g means acceleration due to gravity

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Abhishek Jha 7 years, 1 month ago

G means universal gravitational constant. G

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ANSWER

Draw all the cell present in the human body

Posted by Vrusha Modi 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

What is the kinetic energy of an object

Posted by Rubi Yadav 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Ravinder Kumar 7 years, 1 month ago

The energy of a body due to its motion

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Yogita Ingle 7 years, 1 month ago

Kinetic energy is the energy possessed by an object because of motion. For example, a fast moving pebble can injure a person or break glass pane of window, energy of moving vehicle, a fast moving wind can damage many house, or wind can move blades of wind mill, etc.

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What reaction do you obsreve in the following cases 1.when iron and copper sulphate 2.when iron nail is added to water for few days 3.when Sodium sulphate and chloride 4.when a mixture of iron and sulphur is add to carbon sulphate

Posted by Sambhav Daga 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

We know that carbon dioxide us essential for photosynthesis in pkants .yet, why we cosider it a pollutant

Posted by Sandhya Saini 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Anita Mahala 7 years, 1 month ago

Yes carbon dioxide is essential for photosynthesis in pollutant but still we consider it a pollutant because it is not good for enviroment

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ANSWER

Why does the skin of your fingers shrink when we wash clothes fpr a long time

Posted by Sandhya Saini 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Yogita Ingle 7 years, 1 month ago

Soap solution is a hypertonic solution i.e., more concentrate than our skin cells. As we know, when the cell is immersed in a hypertonic solution, water diffuse out of the cells by osmosis (diffusion of water across semi permeable membrane), due to lower concentration of water outside the ceil. As a result, the cell shrinks. The process is called exosmosis. During washing of clothes, exosmosis takes place in the skin cells. This leads to shrinkage of skin over the fingers while washing clothes for a long time.

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Anita Mahala 7 years, 1 month ago

It is due to the process of exosmosis. Water consentration is more outside the finger and during the process of osmosis the solvent particles moves from higher consentration to lower consentration. Hence water outside is more as compared to finger

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Kaushiki Singh 7 years, 1 month ago

Because of the water?

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ANSWER

What is the significance of electeonic configuration

Posted by Sandhya Saini 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Siddharth Bagora 7 years, 1 month ago

So as to complete inert gases confurogation

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Yogita Ingle 7 years, 1 month ago

Maximum number of electrons in an orbit is calculated by 2n², where ‘n’ is number of orbit and may be equal to 1, 2, 3 , . . . .
Electrons occupy the next orbit only after filling the inner orbit completely.
The maximum number of electrons in outermost orbit will not be more than 8.

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ANSWER

Identify solute and solvent in tincture of iodine

Posted by Rushali Popli 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Siddharth Bagora 7 years, 1 month ago

Solute-iodine Solvent- alcohal

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Sahil Nandode 7 years, 1 month ago

Solute-elemental iodine and solvent =water and ethanol

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ANSWER

Diffrence between layers and broilers

Posted by Rushali Popli 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

An egg laying poultry is called egger or layer whereas broilers are reared for obtaining meat. So a layer should be able to produce more number of large sized eggs, without growing too much. On the other hand, a broiler should yield more meat and hence should be able to grow well.

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ANSWER

Why particals of matter move in brownian motion

Posted by Jatin Chandra 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Anita Mahala 7 years, 1 month ago

Matter which does the brownian motion are generally fluid and they move in brownian because they have kinetic energy and a tendancy to flow

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ANSWER

The fractional change in the value of free fall acceleration g for a particle when it is lifted from the surface to an elevation h(h<<r) is

Posted by Priyanshu Prakash 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

Write five points on suspension

Posted by Keshav Pandey 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

A suspension is a heterogeneous mixture in which solids are dispersed in liquids. The solute particles in suspension do not dissolve but remain suspended throughout the medium. For example Paints, Muddy water chalk water mixtures etc.
Properties of a Suspension

Suspension is a heterogeneous Mixture.
The particles of a suspension can be seen by the naked eye.
The particles of a suspension scatter a beam of light passing through it and make its path visible.
The solute particles settle down when a suspension is left undisturbed, that is, a suspension is unstable. They can be separated from the mixture by the process of filtration.

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ANSWER

What is 2 law of motion

Posted by Ariyan Kumar 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Manish Rajak 7 years, 1 month ago

Applied force is directly proportional to rate of change of momentum of an object i,e. F=m(v-u)/time taken..

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Sant Ram 7 years, 1 month ago

The rate of change of momentum of a body is directly proportional to the applied force and takes place in the direction of force.

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ANSWER

May I know what is notochord

Posted by Aarti Sharma 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Sant Ram 7 years, 1 month ago

A notochord is a long rod like structure that runs along the back of animal seprating nervous tissue from the gut and it also provides a place for muscles to attach for the ease of movements.

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ANSWER

What is ion???

Posted by Aman Verma 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Ishan Mishra 7 years, 1 month ago

Ions are the charged particles . When ions losses electon then it form positively charged cations and when ion gain electron then form negatively charged anions

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Yogita Ingle 7 years, 1 month ago

An atom or molecule when loss or gain electron becomes positively (when loss electrons) or negatively charged(when gain electrons). That atom or molecule is called ion.

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Rubi Yadav 7 years, 1 month ago

An ion is a charge particle that can be negatively or positively charge

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ANSWER

How may i get ready for my science exam

Posted by Rohan Gajju 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Ariyan Kumar 7 years, 1 month ago

Yes

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Rubi Yadav 7 years, 1 month ago

Frst read all the discoveries then the defination and after that numericals

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ANSWER

What isMatter

Posted by Irshad Mohammed 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 1 month ago

Matter : Anything that has weight and occupies space is called matter.
States of matter: Solids: A solid has a definite shape and volume. Examples of solids include ice (solid water), a bar of steel, and dry ice (solid carbon dioxide).
Liquids: A liquid has a definite volume, but takes the shape of its container. Examples of liquids include water and oil.
Gases: A gas has neither a definite volume nor a definite shape. Examples of gases are air, oxygen, and helium.
Plasma is recognized as fourth state of matter.

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Aryan Kumar 7 years, 1 month ago

Any substance that occupies space and have a mass is known as matter

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ANSWER

In science paper have the graphical method of eqations

Posted by Gurpartap Sidhu 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Zahin Patel 7 years, 1 month ago

Ya it has graphical method of equation it shows us the derivation of equation

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Gurpartap Sidhu 7 years, 1 month ago

Answer meeee

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ANSWER

How will you prepare 25g of aqueous solution of having 10 mass percent of sugar?

Posted by Anita Mahala 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

ANSWER

What is pure subtance??

Posted by Aman Verma 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Yogita Ingle 7 years, 1 month ago

Pure Substance: A substance which is made of one kind of particle.
Examples - iron, aluminium, silver and gold.
On the basis of their chemical composition, pure substances are classified as elements and compounds.

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Anita Mahala 7 years, 1 month ago

A substance which has only one type of atoms is called a pure substance

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ANSWER

Define radian.

Posted by Vivek Mishra 7 years, 1 month ago

CBSE > Class 09 > Science