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Explain twinkling of star

Posted by Sanjay Singh 7 years, 1 month ago

1 answers

Stars are twinkle because it is contained of hydrogen and helium atoms when this atoms react with each other they produce multiple atoms. That's why stars are twinkle

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Give the different between atoms and molecules

Posted by Priyanshu Chandola 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

D K 7 years, 1 month ago

1. Atoms are the smallest particles of an element whereas molecules are not the smallest part of an element. 2. Atoms can not be seen even through a powerful microscope whereas molecules can be seen by a powerful microscope. 3. One atom contains the particles of only one element for eg(H) Hydrogen atom, (He) Helium atom while molecules can contain not only particles of only one element but also of more than one element for eg H2O (water) molecule, (O2) Oxygen molecule

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Akanksha Kumari? 7 years, 1 month ago

Atoms are the smallest particle of an element that can take part in a chemical reaction. Molecules are the group of atoms that takes part in a chemical reaction.

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What is orthopoda

Posted by Rockstar Abhi 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Aditya Pandey 7 years, 1 month ago

It is the types of organisms which leave everywhere and eat everything that they have jointed legs

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Why gravity is not in space

Posted by Harsh Rajgor 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Saurav Kumar 7 years, 1 month ago

Gravity from Earth keeps the Moon and human-made satellites in orbit. It is true that gravity decreases with distance, so it is possible to be far away from a planet or star and feel less gravity. But that doesn't account for the weightless feeling that astronauts experience in space. The reason that astronauts feel weightles

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Anusheel Soni 7 years, 1 month ago

Because gravity is something which keeps us attached to something, space is a vast endless vaccum, where possibly can u get attracted?

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How do we know that a person is suffering from a disease

Posted by Dinesh Shetty 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Neha.G Neha 7 years, 1 month ago

Through symptoms

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What is blood vessels

Posted by Nakshatra Chikate 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Vivansh Pandey 7 years, 1 month ago

The blood vessels are the part of the circulatory system, and microcirculation, that transports blood throughout the human body.[1] These vessels are designed to transport nutrients and oxygen to the tissues of the body. They also take waste and carbon dioxide and carry them away from the tissues and back to the heart. Blood vessels are needed to sustain life as all of the body’s tissues rely on their functionality.[2]There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and the tissues; and the veins, which carry blood from the capillaries back toward the heart. The word vascular, meaning relating to the blood vessels, is derived from the Latin vas, meaning vessel. A few structures (such as cartilage and the lens of the eye) do not contain blood vessels and are labeled.

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What are the diffrence between broyler and layer in there managment

Posted by Rocky Vishwakarma 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

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Chromosomes are made up of

Posted by Varsha Manu 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Aayush Jain 7 years, 1 month ago

DNA , RNA and protein

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Neha.G Neha 7 years, 1 month ago

Chromatin networks

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Why are longitudinal waves called pressure waves?

Posted by Neya Saji 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Satyam Kumar 7 years, 1 month ago

because longitudinal wave are those wave in which the particles of the medium vibrate parallel to the direction of the propagation of the wave which involves a process of compression and rarefaction As we know that in compression there is high pressure area and in refraction there is low pressure area this is the reason that the longitudinal wave are also called pressure waves

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Neya Saji 7 years, 1 month ago

Sound waves travels in the form of compressions and rarefactions,which involves change in pressure and volume of the air.thus they are called pressure waves...??

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Difference between Archaebacteria and Eubacteria....

Posted by Sandhya Singh 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Gokul Selvaraj 7 years, 1 month ago

Archaebacteria is the primitive bacteria whereas eubacteria is the true bacteria

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Sciencein hindu

Posted by Dheeraj Mathur 7 years, 1 month ago

CBSE > Class 09 > Science

0 answers

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what is the si unit of frequency

Posted by Keshav Thakur 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

☄️Josna ☄️ 7 years, 1 month ago

0Thank You

Sandhya Singh 7 years, 1 month ago

Hertz (Hz)

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Keshav Thakur 7 years, 1 month ago

hertz

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A ball is thrown vertically upwards returns to thrower. How do kinetic and potential energies of the ball change?

Posted by Ramani Ramani 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Sushma Nirankari 7 years, 1 month ago

When a ball starts moving upward kinetic energy is starting change into potential energy and when it comes back to the thrower potential energy is changed into kinetic energy because K.E=1/2mv square and P.E=mgh

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How are elements formed?

Posted by Yaso Preeti 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Vivansh Pandey 7 years, 1 month ago

The elements formed in these stages range from oxygen through to iron. During a supernova, the star releases very large amounts of energy as well as neutrons, which allows elements heavier than iron, such as uranium and gold, to be produced. In the supernova explosion, all of these elements are expelled out into space.

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Give the test for hydrogen gas

Posted by Yash Sehrawat 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Ziyesha Sourav 7 years, 1 month ago

Take a beaker filled with hydrogen gas and cover it with a plate now get a matchstick neat it and slowly remove the plate if the matchstick burns with a pop sound then it is hydrogen gas

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Explain amphibians

Posted by Rebel Joshi 7 years, 1 month ago

CBSE > Class 09 > Science

4 answers

Palak ?? 7 years, 1 month ago

Hey Rebel...since any of the below answer does not satisfy u....so I just wanted to confirm weather it is amphibia or amphibians......???

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Sandhya Singh 7 years, 1 month ago

The organism who can survive in Land and water are called Amphibians... ??

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Om Narayan Rajwade 7 years, 1 month ago

Those who Live in land or water but they need water for Fertilization

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Yash Pratap Singh 7 years, 1 month ago

Type of animals which can live on both land and water

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In case of fire a fire menshut off the mAIn electric supply for the area before the use of water house. Why

Posted by Subhash Gulati 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Mansha Sard 7 years, 1 month ago

This is because water is a very good conductor of elecricity and catches It very easily he shut off the main switch that he may not get an eleceic shock??

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Evporation causes cooling.comment on this statement

Posted by J M 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Sachin Mahto 7 years, 1 month ago

When a liquid evaporates,it takes heat enegy from the surface and the surroundings which causes cooling in the surroundings.Thus ,evaporation causes cooling

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Yash Pratap Singh 7 years, 1 month ago

Wearing sporeful shirts in summer

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Which gas is called dry ice ?why

Posted by Priyaanshu Mal!Yan 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Raja Praneetam 7 years, 1 month ago

Solid carbondioxide is called dry ice. It is called dry ice because the carbondioxide is solidified or dried

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A diver is able to cut through water in a swimming pool . Which property of matter does this observation show . Explain in brief.

Posted by Pratik Deb Barma 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Rrrrrrrrrkkkk Sfgvtbbh 7 years, 1 month ago

There is space between the particles of water the diver was able to cut through out the water And the property here used is compressibility

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Ashray Rana 7 years, 1 month ago

The property of matter is ,particles of matter attract them with different type of forces

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Name the division which is also known as amphibians of plant Kingdom

Posted by Harsh Bishnoi 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Akanksha Kumari? 7 years, 1 month ago

Bryophyta is known as the amphibians of kingdom plantae because they are found both on land and water

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Adwaith Sonu 7 years, 1 month ago

AMPHIBIA

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Harsh Bishnoi 7 years, 1 month ago

Bryophyta

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Write two property of coolides

Posted by Archana Trivedi 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Pranav Devnath 7 years, 1 month ago

Coolides is hetergeneous. The size of collide particles is too small to be individually seen by naked eye.

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Why naphthalene ball disappear

Posted by Manav Saxena 7 years, 1 month ago

CBSE > Class 09 > Science

4 answers

Pratik Deb Barma 7 years, 1 month ago

Because sublimation is a process in which solid convert into gas directly

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Pranav Devnath 7 years, 1 month ago

Naphthalene ball undergo sublimation due to which it convert directly go into vapour and disslove into air without leaving any solid.

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Sulochana Jani 7 years, 1 month ago

Because of sublimation

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Ishit Gadia 7 years, 1 month ago

Because of sublimation

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Which solution is used to dissole gold

Posted by Ganesh Wagh 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Pranav Devnath 7 years, 1 month ago

"Royal water" And "King water"

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What is isotope and it application

Posted by Deepika Dabas 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Pranav Devnath 7 years, 1 month ago

Radiocarbon dating, which measure the age of carbon bearing items, uses a radioactive isotope known as carbon-14. In medicine , Gamma rays emitted by radioactive Elements are used to detect tumors inside the human body..

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Why the white shirt makes us feel cool in winters?

Posted by Ankit Pal 7 years, 1 month ago

CBSE > Class 09 > Science

1 answers

Pratik Deb Barma 7 years, 1 month ago

Because white shirt absorb less heat

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Acetic acid chemical name

Posted by Abhishek Kumar 7 years, 1 month ago

CBSE > Class 09 > Science

2 answers

Akanksha Kumari? 7 years, 1 month ago

It is also known as methanecarboxylic or ethanoic acid. Acetic acid is the chemical name of vinegar

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Ashray Rana 7 years, 1 month ago

Vinegar

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What is the valency of chlorine negative?

Posted by Abcd E 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Abcd E 7 years, 1 month ago

But the valency of chlorine is also -1 then how the valency of chlorine negative will also be -1

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Aayush Chandak 7 years, 1 month ago

-1

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Sohit Mandal 7 years, 1 month ago

Because it is non metal and non metal always gain electron due to which the the valency of electron is negative

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What causes winds

Posted by Gungun Sharma 7 years, 1 month ago

CBSE > Class 09 > Science

3 answers

Akanksha Kumari 7 years, 1 month ago

heating of air occur by direct water body.it produce conventic current. Hot air rise upward. It form an area of low pressure. Air from area of high pressure will move towards that area producing wind or breaze

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Dheeraj Singh 7 years, 1 month ago

the high and low air pressure causes wind

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Yogita Ingle 7 years, 1 month ago

The uneven cooling of land and sea and the building of the low and high pressure area causes the air to move from a high pressure are to a low pressure area. This movemnet of the air from one region to the other region caused winds.

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Calculate the mass% of each element in sodium chloride in 1 mole of it.

Posted by Sachin Mahto 7 years, 1 month ago

CBSE > Class 09 > Science