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Isotopes are variants of a particular chemical element which differ in neutron number, and consequently in nucleon number. All isotopes of a given element have the same number of protons but different numbers of neutrons in each atom. Isobars are atoms of different chemical elements that have the same number of nucleons. Correspondingly, isobars differ in atomic number but have the same mass number. An example of a series of isobars would be ⁴⁰S, ⁴⁰Cl, ⁴⁰Ar, ⁴⁰K, and ⁴⁰Ca.

1Thank You

Maanya Gupta 3 years, 6 months ago

Isotope are those atoms who have different mass numbers but same atomic number while isobars are those atoms who have different atomic number but mass number is same Isotopes are atoms of Same element but isobars are atoms of different elements

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ANSWER

The symbol of cadmium is

Posted by Nidhi Tiwari 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

I Am Snx 3 years, 6 months ago

If u mean cadium it is Cd

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Kumari Kriti 3 years, 6 months ago

The symbol of calcium is called CL

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ANSWER

The symbol of cadium is

Posted by Nidhi Tiwari 3 years, 6 months ago

CBSE > Class 09 > Science

3 answers

I Am Snx 3 years, 6 months ago

The symbol of cadium is Cd

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Farhan Ahmed 3 years, 6 months ago

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Billa Raja Kuch Nhi 3 years, 6 months ago

Lawda

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ANSWER

Name the si unit of pressure

Posted by Learn Book 3 years, 6 months ago

CBSE > Class 09 > Science

4 answers

Digvijay Singh ?? 3 years, 6 months ago

Pascal

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Jiya Yadav 3 years, 6 months ago

Pascal

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Kumari Kriti 3 years, 6 months ago

SI unit of pressure is called Pascal (Pa).

2Thank You

Khushi Jha 3 years, 6 months ago

Different between molecule and compound

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ANSWER

Different between acute and cure

Posted by Koina Shiyal 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Suchitra Sen 3 years, 6 months ago

Acute: the disease which lasts for few days, are called acute. Ex cough and cold.... Chronic:the disease which lasts for many days are called chronic.Ex.AIDS, TB....

1Thank You

ANSWER

What name is given to pair of atom such as 40/20 ca and 40/18 ar??

Posted by Shivani Sharma 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Devika K 3 years, 6 months ago

Isobars

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Raman Kumar Rajeev 3 years, 6 months ago

Isotopes

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ANSWER

write all the three laws of motion

Posted by Shreeja Sasi 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Baby Bushra Siddiqe 3 years, 6 months ago

FIRST LAW OF MOTION: it state that the object is rest will stay at rest and an object in motion will stay in motion even external force applied on it. It is also known as law of inertia. SECOND LAW OF MOTION: it state that the rate of change of momentum of an object is proportional to the applied unbalanced force in the direction of force. THIRD LAW OF MOTION: It state that when one object exert a force on another object , the second object immediately exerts a force back on the first object.

1Thank You

Raman Kumar Rajeev 3 years, 6 months ago

v=u-at s=ut+1/2at^2 v^2=u^2+2as

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ANSWER

What is biogeochemical

Posted by Yash Garg 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Koina Shiyal 3 years, 6 months ago

any of the natural pathway by elements of living matter are circulated

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ANSWER

what is chronic diseases

Posted by Aman Thakur 3 years, 6 months ago

CBSE > Class 09 > Science

5 answers

Jiya Yadav 3 years, 6 months ago

Chronic diseases are thise disease which lasts for a long time in our body...Some of chronic diseases are listed below-: 1) Respiratory disease. 2) Pneumonia. 3) Tuberculos. 4) Asthma. 5) Arthritis.

1Thank You

Kumari Kriti 3 years, 6 months ago

Chronic diseases are long time to recover. Example=cancer, thyroid etc.

1Thank You

Shubham Kumar 3 years, 6 months ago

Chronic diseases are long terms disease . Like a diabetes

1Thank You

G G. Vinutha 3 years, 6 months ago

Long durational diseass

2Thank You

Taniya Verma 3 years, 6 months ago

Chronic diseases are long lasting disease which effects body dramatically,like cancer, Diabetes etc.

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ANSWER

Timetable for class 7

Posted by Ramitha S 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Shubham Kumar 3 years, 6 months ago

आप क्लास सेवंथ में तो आपको 2 घंटे साइंस 2 घंटे में एक एक घंटा को सोशल साइंस इंग्लिश हिंदी पर बिताना है ठीक है

2Thank You

ANSWER

Under what conditions is the . magnitude of average velocity of an object is equal to average speed

Posted by Swati Dubey 3 years, 6 months ago

CBSE > Class 09 > Science

4 answers

Maanya Gupta 3 years, 6 months ago

Linear motion

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Kartik Pal 3 years, 6 months ago

When displacement is equal to distance travelled

1Thank You

G G. Vinutha 3 years, 6 months ago

When they are in straight line

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Pardeep Kumar 3 years, 6 months ago

he wer sa that

1Thank You

ANSWER

What is the formula for elastic potential energy

Posted by Ayush Pandey 3 years, 6 months ago

CBSE > Class 09 > Science

5 answers

Nitin Jain 3 years, 6 months ago

Mgh

1Thank You

Srishti Tripathi 3 years, 6 months ago

Mgh

1Thank You

Anshu Agrawal 3 years, 6 months ago

Mgh

1Thank You

Riya Sharma💜🤞 3 years, 6 months ago

M × g × H Is the formula for elastic potential energy.

2Thank You

Vidushi Garg 3 years, 6 months ago

M×g×H

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ANSWER

What is the difference between atomic mass and gram atomic mass of an element also the difference between mass number

Posted by Ayush Pandey 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Vidushi Garg 3 years, 6 months ago

Atomic mass is the total mass present in the atoms of a element. Gram atomic mass is if that same atomic mass is converted to grams and mass number is defined as the complete amount in protons and neutrons in nucleus of an atom

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ANSWER

900 9800 joules of energy was spent to raise a mass of 50 kilogram the mass was raised to the height ?

Posted by Bhumi Sharma 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Ayush Pandey 3 years, 6 months ago

18019.6m - height

1Thank You

ANSWER

Difference between centripetal and centrifugal force

Posted by S M 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Satyam Kumar 3 years, 6 months ago

The force which exert away from centre is called centrifugal force

3Thank You

Satyam Kumar 3 years, 6 months ago

The force which exert towards centre is called centripetal force

2Thank You

ANSWER

Explain dalton atomic theory

Posted by Tanya Sharma 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Nandani Priya 3 years, 6 months ago

Based upon laws of chemical combination dalton Atomic theory provides an explanation for the law of conservation of mass and laws of contant composition

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Kiikii Panda_B00 3 years, 6 months ago

All matter is made of very tiny particles called atoms which participates in chemical reactions

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ANSWER

Define mation

Posted by Suraj Pandat 3 years, 6 months ago

CBSE > Class 09 > Science

5 answers

Taran Boparai 3 years, 6 months ago

Motion - when a thing is moving , it is said that a thing is in motion।

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Bhavya Rajput 3 years, 6 months ago

AIDS- Acquired immuno deficiency syndrome

1Thank You

Vidhi Agarwal 3 years, 6 months ago

Want to say motion?

1Thank You

Suraj Pandat 3 years, 6 months ago

Write the expanded form of aids

4Thank You

Suraj Pandat 3 years, 6 months ago

Define mation

2Thank You

ANSWER

What mechanism does the vaccine follow to prevent the infections?

Posted by Anushka . 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Vidhi Agarwal 3 years, 6 months ago

Hii anushka? The process is known as immunisation.. in this process v basically fool our immune system.. via injection v inject very very weak or almost dead viruses in our body so that our immune system got to know about it.. v introduce such viruses or bacteria to our immune system so that it can prepare antibodies against it and identify it in future whenever the same virus enters in our body our immune system had already prepared antibodies against it and now had known that what type of antiboides it require... This is how this process works... Hope it helps u my dear mate..??

5Thank You

ANSWER

Assertion or reason question

Posted by Mohd Haseeb 3 years, 6 months ago

CBSE > Class 09 > Science

0 answers

ANSWER

Explain Bohr's model of an atom

Posted by A N 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Vathsala Prabhu 3 years, 6 months ago

An atom consists of heavy positively charged nucleus. The whole mass of the atom is concentrated in the nucleus. The electrons in an atom revolve around the nucleus in definite circular paths called orbits or energy level. Each energy level is associated with definite amount of energy. The change in energy takes place when electron jumps from one energy level to another energy level.

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ANSWER

Can we reproduct on 15 year.

Posted by Soxo Gogo 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Steny Mathew 3 years, 6 months ago

Yes

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ANSWER

Two balls of the same size but the different materials,rubber and iron are kept on a smooth floor of a moving train. The brakes are applied suddenly to stop the train will the ball start rolling? If so in which direction will they move with the same speed? Give reasons for your answer.

Posted by Diya Verma 3 years, 6 months ago

CBSE > Class 09 > Science

1 answers

Trisha Kumari 3 years, 5 months ago

Answer: When the train is stopped suddenly, then it comes in the state of rest but the balls remain in the state of motion. So, due to inertia of motion, the balls move in the forward direction. As the balls are of same size but of different materials that means their mass will be different.

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ANSWER

Define the atomic mass unit?

Posted by Roshni Meerchandani 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Drashya Shah 3 years, 6 months ago

Hope it help????

1Thank You

Drashya Shah 3 years, 6 months ago

An atomic unit of mass is defined as accurately 1/12 the mass of a carbon-12 atom.

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ANSWER

Homogenous and meterogenous d/f

Posted by C B 3 years, 6 months ago

CBSE > Class 09 > Science

3 answers

Tanishq Kumar 3 years, 6 months ago

Homogeneous mixture- The mixture which has the same composition throughout the mixtures is called homogeneous mixture. It cannot be separated by physical methods. Heterogeneous mixture- The mixture which has the different composition throughout the mixture is called heterogeneous mixture. It can be separated by physical methods.

0Thank You

Eshaan S 3 years, 6 months ago

Heterogenous you mean right... in 2nd part...

0Thank You

Rishabh Kothari 3 years, 6 months ago

Homogeneous Has a uniform composition throughout it's mass whereas heterogeneous has non- uniform composition through out its mass. Homogeneous does not have visible boundaries of separation whereas heterogeneous has visible boundaries of separation.

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ANSWER

State cell theory.Who proposed it ?

Posted by Pawandeep Kaur 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Jasmeet Kaur 3 years, 6 months ago

Cell theory is:- 1. All living things are made up of cells. 2. Cells are the basic building blocks of life. 3. All cells come from preexisting cells created through the process of cell division.

1Thank You

Gäyàtrî Rawat 3 years, 6 months ago

Cell theory was proposed by Scheilden and Schwann

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ANSWER

Write drawbacks of Rutherford's model of atom

Posted by Pawandeep Kaur 3 years, 6 months ago

CBSE > Class 09 > Science

5 answers

Drashya Shah 3 years, 6 months ago

Hope it help

1Thank You

Drashya Shah 3 years, 6 months ago

He explained that the electrons in an atom revolve around the nucleus in well-defined orbits. Particles in a circular orbit would experience acceleration. Thus, the revolving electron would lose energy and finally fall into the nucleus. But this cannot take place as the atom would be unstable and matter would not exist in the form we know.

2Thank You

Drashya Shah 3 years, 6 months ago

I think u ll get it there

1Thank You

Drashya Shah 3 years, 6 months ago

Pg 48..right side last para

1Thank You

Drashya Shah 3 years, 6 months ago

It is there in the book ...ncert

2Thank You

ANSWER

Rutherford alpha particle scattering experiments showed that

Posted by Mohd Haseeb 3 years, 6 months ago

CBSE > Class 09 > Science

4 answers

Uday Gola 3 years, 6 months ago

in your science ncert book?

1Thank You

Harpreet Singh 3 years, 6 months ago

1Thank You

Rishabh Kothari 3 years, 6 months ago

Rutherford's alpha particles scattering showed the three major function of the nucleus 1) Since most of the alpha particles pass straight, this show that the nucleus has lots of space in it. 2) Since some alpha particles deflects to smaller and larger angles, this shows that the nucleus is a positively charged particles. 3) Since most of the alpha particles rebounds in the same path, this shows that the nucleus is very hard and dense.

1Thank You

Aditi Kumari 3 years, 6 months ago

Experiment were then carried or to find out how electron proton and neutron were arranged in an atom . It was Rutherford's alpha particles scattering experiment which led to the discovery of a small positively charged particles containing all the protons and neutrons. When fast moving alpha particles are allowed to strike a very thin gold foil in vaccum it is found that 1‐most of the alpha particles pass straight through the gold foil without any deflection from their original path. 2‐a few particles are deflected through small angles and a few are deflected through large angles. 3‐a very few alpha particles completely rebound on hitting the gold foil and turn back on their path.

2Thank You

ANSWER

Why are antibiotics effective against bacteria but not against viruses? Explain

Posted by Tosayanti Bhoi 3 years, 6 months ago

CBSE > Class 09 > Science

2 answers

Rishabh Kothari 3 years, 6 months ago

Antibiotics helps in stopping the usage of bio- chemical activities by the bacterias only. Virus enter the human body and uses the host cell. This would harm their own human body. That is the reason antibiotics are effective against bacteria only

2Thank You

Vidushi Chordia 3 years, 6 months ago

Antibiotics cannot kill viruses because viruses have different structures and replicate in a different way than bacteria. Antibiotics work by targeting the growth machinery in bacteria (not viruses) to kill or inhibit those particular bacteria.

2Thank You

ANSWER

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