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What are isobars,isotopes,isoelectrons,isotones and isosteres

Posted by Ashawani Kumar 7 years, 5 months ago

1 answers

Sahil Bhattad 7 years, 4 months ago

Isotopes means the element has same atomic number but different mass number. Isobars means different elements can have same mass number but different atomic number. . Refer to chapter structure of an atom

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Calculate the number of moles of magnesium present in a magnesium ribbon weighing 12 gm. Moler atomic mass of magnesium is 24 gm/mol.

Posted by Priyanka Jayaswal 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Senthil Kumaran 7 years, 5 months ago

24 dived by mass of 12 =2

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Father of elements

Posted by Priya Kesava 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Ayesha Siddiqui 7 years, 5 months ago

Dmitri mandeelev

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Who is the first scientists

Posted by Pavan Mehta 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Tirtha Phade 7 years, 5 months ago

William whewell is the worlds first scientist

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Who is the chandn sharma

Posted by Pavan Mehta 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Nitin Jaat Ahlawat 7 years, 4 months ago

Dad

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Nitin Jaat Ahlawat 7 years, 4 months ago

Your daf

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Why a truck or a motorbus has much wider tyres

Posted by Badal Laur 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Tirtha Phade 7 years, 5 months ago

The truck and motor bus has wider tyres because as more the area less the pressure . as the area increase the pressure will decrease , so there will be less need to apply more pressure to handle the vehicle ....the vehicle will move smoothly

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Yogita Ingle 7 years, 5 months ago

A truck or motor bus has much wider tires to reduce the pressure exerted by it as more the area more will be the pressure exerted and less the area less will be the pressure exerted.The truck and motorbus have wider tyres with respect to the property that "more the area ,less the pressure." As the area is more the pressure will decrease , so there will be less need for applying more pressure to handle the vehicle.The vehicle will move smoothly.

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Why is it easier to carry a school bag with wide straps than one with a thin strap?give relevant mathematical expression to support your answer.

Posted by Alima Khan 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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Tabulate the difference in the characteristics of state matter.

Posted by Mayuri Shewale 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Tirtha Phade 7 years, 5 months ago

.NO Property Solid Liquid Gases 1. Shape They Have definite shape They do not have definite shape They do not have definite shape 2. Volume They have definite volume They do not have definite volume They do not have definite volume 3. Density They have high density. Liquids have less density than solids. Liquids have least density. 4. Kinetic energy of particles. Least More than solids Maximum 5. Compressibility Negligible Low High Rigidity: It is the property of matter to resist the change of its shape. Compressibility: It is the property of matter in which its volume is decreased by applying force. Fluidity: It is the ability of matter to flow. Filling a gas container: On filling a gas takes the shape of the container. Shape: Having definite boundaries. Kinetic energy: It is the energy possessed by the particles of matter due to its motion. Density: It is the ratio of mass with per unit volume

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A stone is dropped from the edge of the roof. (a)How long its take to fall 4.9m. (b)How fast does it move at the end of the fall. (c)How fast does it move at the end of 7.9m. (d)What is the acceleration after 1second and after second.

Posted by Rahul Kathayat 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Write an expression for the kinetic energy of sn object

Posted by Manoranjan Sahoo 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

What is antibiotics

Posted by Ayush Kumar 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Ayush Kumar 7 years, 5 months ago

Antibiotics are used for killing the bacterial cells because they make cell wall to protect themselves but antibiotics kill them from making their cell walls

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How does bryophyta and pteridophyta reproduces???

Posted by Kalpana Choudhary 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Kalpana Choudhary 7 years, 5 months ago

Thanks?

1Thank You

Gagan Pal 7 years, 5 months ago

By asexual reproduction

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Are you mad! Sorry

Posted by Ananta Pant 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Kirti Singh 7 years, 4 months ago

You and your ? are mad

1Thank You

Ananta Pant 5 years, 11 months ago

Nooo

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What is force si unot

Posted by Tosif Ansari 7 years, 5 months ago

CBSE > Class 09 > Science

4 answers

Kirti Singh 7 years, 4 months ago

Force =mass*acceleration =Kg*m/s.square =Newton =N

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Ashawani Kumar 7 years, 5 months ago

newton(N).

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Yashraj Kumar Gupta 7 years, 5 months ago

NEWTON

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Aryan Tomar 7 years, 5 months ago

Newton

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Difference between diaton and protozoans

Posted by Shaivya Tiwari 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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W what is the full form of IUPAC

Posted by Ayush Kumar 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Miss Angel Barsha 7 years, 4 months ago

International Union of Pure and Applied Chemistry

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Aryan Tomar 7 years, 5 months ago

International Union pure applied chemistry

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What is warm blooded animal

Posted by Subhash Chandra 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Kalpana Choudhary 7 years, 5 months ago

Those animals who can not change their body temperature according to the surroundings... Eg– human beings

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What is the difference between Na and Na+ in terms of number of electrons

Posted by Jigar Desai 7 years, 5 months ago

CBSE > Class 09 > Science

2 answers

Ashawani Kumar 7 years, 5 months ago

Na means symbol of sodium wherever Na+ means sodium looses its electron.

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Aryan Tomar 7 years, 5 months ago

Na means the symbol of sodium wherever Na+ means sodium gain a charge

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Scientific name of tiger

Posted by Satvee Virani 7 years, 5 months ago

CBSE > Class 09 > Science

3 answers

Shyamli Gupta 7 years, 5 months ago

It is panthera tigris

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Aryan Tomar 7 years, 5 months ago

Panthera is a specific name and tigris is a generic name

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Priyansh Shrivastava 7 years, 5 months ago

Panthera tigris

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What does the odometer of an automodile measure?

Posted by V.Aditya Vardhan 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Abu Zar 7 years, 5 months ago

The distance travelled by the automobile

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Why there is gravitational force between two object

Posted by Saurabh And Shekhar Jha 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Neymar Jr 7 years, 5 months ago

It is not gravitational force. It is Universal Gravitation Constant and it's value is 6.67 multiply 10 raise to power -11Nm square per kilogram square

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Is work done can be negative

Posted by Soham Bhattacharya 7 years, 5 months ago

CBSE > Class 09 > Science

4 answers

Ashawani Kumar 7 years, 5 months ago

Yes.

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Shyamli Gupta 7 years, 5 months ago

Absolutely yes

1Thank You

Saurabh And Shekhar Jha 7 years, 5 months ago

Yes

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Rutuja Jambhulkar 7 years, 5 months ago

Yes

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The mass of the earth is 6*10 to the power 24kg and that of moon is 7.4*10 to the power 22kg. If the distance between the earth and the moon be 3.84*10 to the power 5km then calculate the force exerted by the earth on the moon

Posted by Khushi Mishra 7 years, 5 months ago

CBSE > Class 09 > Science

0 answers

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Rizobium bacteria

Posted by Sujit Patel 7 years, 5 months ago

CBSE > Class 09 > Science

1 answers

Yogita Ingle 7 years, 4 months ago

Rhizobium (plural: Rhizobia) is the nitrogen fixing bacteria present mainly in the soil. The Rhizobia chemically convert the nitrogen from the air to make it available for the plant.These bacteria live in symbiotic relationship with leguminous plants. The Rhizobia live in nodules in the roots of the plant. These bacteria convert atmospheric nitrogen to nitrates and nitrites which can be used by the plants directly. Nitrogen fertilizers are not required.

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1 joule is equal to how many erg

Posted by Reshma Phadke 7 years, 5 months ago

CBSE > Class 09 > Science