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Posted by Ankit Yadav an hour ago

CBSE > Class 09 > Science

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Define force and momentum ?

Posted by Khusi Pradhan 21 hours ago

CBSE > Class 09 > Science

1 answers

Akash Kumar 21 hours ago

A push and pull an object is called force AND The product of mass and velocity of an object is called momentum

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Compute the mathematical formula of calculating potential energy

Posted by Jagyaseni Behera 21 hours ago

CBSE > Class 09 > Science

2 answers

Baalveer Returns 2 hours ago

M×G×H where m is mass g is gravitational force h is height

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Priyash Raj 8 hours ago

P. E = M×G×H where m is mass g is gravitational force h is height

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Joseph jog from one and a to other b of a straight 300m road in 2min 30s and then

Posted by Nihal Rajak 1 day, 3 hours ago

CBSE > Class 09 > Science

2 answers

Mohit Tanwar 22 hours ago

Its depends on Joseph

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Anushk Ramesh 22 hours ago

Yo bro

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Why does protons of a atom doesn't repel each other like alfa rays repels the nucleus

Posted by Utkarsh Chaturvedi 1 day, 4 hours ago

CBSE > Class 09 > Science

2 answers

Saloni Harinkhede 2 hours ago

Because the simlar charge reepal each other

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Priyash Raj 8 hours ago

Because the simlar charge reepal each other

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experiment on physics calculation of least count

Posted by Asma Raza 1 day, 5 hours ago

CBSE > Class 09 > Science

0 answers

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Name two air borne diseasr

Posted by Abhijeet Tiwari 1 day, 6 hours ago

CBSE > Class 09 > Science

3 answers

Priyash Raj 8 hours ago

Corona, chicken pox

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Mohit Tanwar 1 day ago

Covid -19 , cold

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Pragati Yadav 1 day ago

Asthama , covid-19

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What is meant by a substance.

Posted by Neelakshi Singh 1 day, 8 hours ago

CBSE > Class 09 > Science

2 answers

Ayushi Suryavanshi 1 day, 5 hours ago

Any substance is said to be pure if and only if it is made up a single type of particles means all the particles of that substance should be of same chemical nature. For example water,sugar,salt, sodium,tin, etc.

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Rishika Dhindwal 1 day, 7 hours ago

A substance is a pure single form of matter . It cannot separated into other kinds of matter by any physical process.

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Where are peroxisomes found??

Posted by Palak Goyal 1 day, 9 hours ago

CBSE > Class 09 > Science

1 answers

Priyal Gupta 1 day, 2 hours ago

Peroxisomes are found in the cytoplasm of a eukaryotic cell

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If object in height that the potential energy. If the object no height and touch to earth surface then which energy on object?

Posted by Arpit Srivastav 1 day, 12 hours ago

CBSE > Class 09 > Science

1 answers

Palak Goyal 1 day, 9 hours ago

Kinetic energy

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Your younger brother observes some mosquitoes sucking juices of cut fruit pieces, though it is common knowledge that mosquitoes suck blood of humans. How will you explain this behavior to him?

Posted by Ramesh Gemnani 1 day, 16 hours ago

CBSE > Class 09 > Science

0 answers

ANSWER

State the name and type of Force which is responsible for the formation of tides in the sea

Posted by Nisha Murali 1 day, 21 hours ago

CBSE > Class 09 > Science

1 answers

Rishika Dhindwal 1 day, 7 hours ago

Gravity

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What is an ideal bday wish for some

Posted by Sachi Khushalani 1 day, 20 hours ago

CBSE > Class 09 > Science

0 answers

ANSWER

According to Newton's third laws every action has equal and opposite reaction then why are able to carry the things like glass,bag, etc .??

Posted by Manish Kumar 2 days, 1 hour ago

CBSE > Class 09 > Science

0 answers

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Give Note on Monera kingdom

Posted by Awaniti Jaiswal 2 days, 10 hours ago

CBSE > Class 09 > Science

2 answers

Kajal Yadav 1 day, 22 hours ago

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Arpit Shukla 2 days ago

Don't post personal information, mobile numbers and other details.
Don't use this platform for chatting, social networking and making friends. This platform is meant only for asking subject specific and study related questions.
Be nice and polite and avoid rude and abusive language. Avoid inappropriate language and attention, vulgar terms and anything sexually suggestive. Avoid harassment and bullying.
Ask specific question which are clear and concise.

Remember the goal of this website is to share knowledge and learn from each other. Ask questions and help others by answering questions.

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Explain bohr,s model of atom

Posted by Prachi Verma 2 days, 21 hours ago

CBSE > Class 09 > Science

1 answers

Akshat Holland Puth 1 day, 9 hours ago

According to Bhor's Model of an Atom - 1) Only some special orbits called discrete orbits are allowed in an atom. 2) While revolving around the discrete orbits electrons do not radiate energy. 3) The shells or orbits in an atom are known as energy levels and are named as n= K, L, M, N and so on or 1,2,3,4...

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Atom and molecules notes

Posted by Bhupesh Yadav 2 days, 22 hours ago

CBSE > Class 09 > Science

2 answers

Kripa Daga 2 days, 10 hours ago

•Go in science column •Select chapter atoms and moleclues •select cbse revision notes •click on the row •scroll down and you have your notes •thanks

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Kripa Daga 2 days, 10 hours ago

Laws of Chemical Combination Limitation of “Law of definite proportion” This law does not hold good when the compound is obtained by using different isotopes of the combining elements. 2. John Daltons Atomic Theory Using his theory, Dalton rationalized the various laws of chemical combination which were in existence at that time. However, he assumed that the simplest compound of two elements must be binary. 3. Atoms, Molecules, Ions & Chemical Formula Atom An atom is the smallest particle of an element which can take part in a chemical reaction. It may or may not exist freely. Each atom of an element shows all the properties of the element. Molecule The smallest particle of matter (element or compound) which can exist in a free state. The properties of a substance are the properties of its molecules. MOLECULES OF ELEMENT : The molecules of an element are constituted by the same type of atoms. MOLECULES OF COMPOUND: Atoms of different elements join together in definite proportions to form molecules of compounds. (hetero atomic molecules) ATOMICITY: The number of atoms contained in a molecule of a substance (element or compound) is called its atomic Element Formula Atomicity Ozone O3 3 Phosphorus P4 4 Sulphur S8 8 Oxygen O2 2 Based upon atomicity molecules can be classified as follows. Monoatomic molecules: Noble gases helium, neon and argon exist as He Ne and Ar respectively. Diatomic molecules: Triatomic molecules: SYMBOLS The abbreviation used to represent an element is generally the first letter in capital of the English name of element. Oxygen O Nitrogen N When the names of two or more elements begin with the same initial letter, the initial letter followed by the letter appearing later in the name is used to symbolize the element Barium Ba Bismuth Bi Symbols of some elements are derived from their Latin names ELEMENT LATIN NAME SYMBOL Sodium Natrium Na Copper Cuprum Cu Potassium Kalium K Iron Ferrum Fe Mercury Hydragyrum Hg Tungsten Wolfram W Polyatomic Ion : A group of atoms carrying a charge is as polyatomic ion. Eg. Valency : The number of electrons which an atom can lose , gain or share to form a bond. OR It is the combining capacity of an atom of the element. Chemical Formula : A chemical formula is a short method of representing chemical elements and compounds. Writing a Chemical Formula -CRISS-CROSS rule RULES > All subscripts must be reduced to lowest term (except for molecular or Examples CATION ANION FORMULA NAME Aluminium sulphate Ca Calcium bicarbonate Ammonium chloride Sodium carbonate Magnesium hydroxide Sodium phosphate 4. Mole Concept The mole (mol) is the amount of a substance that contains as many elementary entities as there are atoms in exactly 12.00 grams of The Avogadro constant is named after the early nineteenth century Italian scientist Amedeo Avogadro. GRAM MOLECULAR MASS Gram molecular mass is the mass in grams of one mole of a molecular substance. Ex: The molecular mass of is 28, so the gram molecular mass of is 28 g. ATOMIC MASS UNIT An atomic mass unit or amu is one twelfth of the mass of an unbound atom of carbon-12. It is a unit of mass used to express atomic masses and molecular masses. Also Known As: Unified Atomic Mass Unit (u). MOLECULAR MASS : A number equal to the sum of the atomic masses of the atoms in a molecule. The molecular mass gives the mass of a molecule relative to that of the 12 C atom, which is taken to have a mass of 12. Examples: The molecular mass of is approximately 30 or . Therefore the molecule is about 2.5 times as heavy as the 12C atom or about the same mass as the NO atom with a molecular mass of 30 or (14 +16). 5. Molar Mass & Avogadro Constant

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State and prove the law of conservation of energy

Posted by Divyanshi Mahajan 3 days, 1 hour ago

CBSE > Class 09 > Science

2 answers

Arpit Srivastav 1 day, 12 hours ago

Energy neither be created nor be destroyed only change one form to another.

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Gautam Nayak 2 days, 23 hours ago

Don't post personal information, mobile numbers and other details.
Don't use this platform for chatting, social networking and making friends. This platform is meant only for asking subject specific and study related questions.
Be nice and polite and avoid rude and abusive language. Avoid inappropriate language and attention, vulgar terms and anything sexually suggestive. Avoid harassment and bullying.
Ask specific question which are clear and concise.

Remember the goal of this website is to share knowledge and learn from each other. Ask questions and help others by answering questions.

2Thank You

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One day in moon is how many days in earth

Posted by Jagyaseni Behera 3 days, 2 hours ago

CBSE > Class 09 > Science