Class 9

Science
Adden On 2019-Feb-13
1 Books
(18 Reviews)
Class 9 NCERT Science
Matter in Our Surrounding
Chemistry is all around us. Chemical reactions are seen in plants and animals which results in the formation of substances and it can be used to treat disease, Let's know about chemistry around us.

The chapter completely depicts the importance of matter based on their physical properties and chemical nature. Physical Nature of Matter which is included at the end of this chapter helps a student to relate the facts about matter in our daily lives. This chapter explains that Matter is made up of particles and how small are these particles of matter. This will provide furthermore clarity to student making them understand about the physical nature of matter. The chapter Matter in Our Surroundings comprises of physical properties of matter, states of matter – Solid, liquid and gas, characteristics of particles of matter, changing one state to another state – melting, freezing & evaporation, Evaporation, effect of pressure and temperature, and the factors affecting the rate of evaporation.

Is Matter Around Us Pure
World of Living that holds weightage of 23 marks. The solutions given for the questions in this chapter will provide the students a set of tools with which they can understand about the chapter Is Matter Around Us Pure in a better way.

The chapter completely depicts the importance of matter based on their physical properties and chemical nature. Physical Nature of Matter which is included at the end of this chapter helps a student to relate the facts about matter in our daily lives. This chapter explains that Matter is made up of particles and how small are these particles of matter. This will provide furthermore clarity to student making them understand about the physical nature of matter. The chapter Matter in Our Surroundings comprises of physical properties of matter, states of matter – Solid, liquid and gas, characteristics of particles of matter, changing one state to another state – melting, freezing & evaporation, Evaporation, effect of pressure and temperature, and the factors affecting the rate of evaporation.

Atoms and Molecules
Let's explore Atoms and Molecules.The simple and comprehensible solutions will help the learners to understand the theoretical and practical aspects of topics such as laws of chemical combination including law of conservation of mass, law of constant proportions.

The chapter 3 of class 9 Science, Atoms and Molecules, depicts about the ideas of divisibility of matter. As one goes further through the chapter 3, Atoms and Molecules, an important topic called what is a molecule? molecules of compounds, molecules of elements, what is an ion and much more will be taught. Law of conservation of mass and energy, laws of chemical combination, law of constant proportions and Dalton’s atomic theory. Size, symbol and mass of an atom, molecules of elements and compounds & ions (cation & anions). You will learn how to write chemical formula of simple compounds, molecular mass and mole concepts, formula unit mass.

Structure of the Atom
n this chapter, an attempt is made to explain that atoms are not indivisible. The topic Charged Particles in Matter depicts that an atom is divisible and contains charged particles.

In this chapter, you will study interesting topics like Proposal of various scientist of atomic model – J J Thomson‘s model and also the drawbacks of the same. Charged Particles in any matter topic in this chapter conveys the concept that an atom is divisible and contains charged particles. Topics such as Rutherford’s experiment, concluded model of an atom and drawbacks. Bohr’s atom’s model and correction of Rutherford’s model, distributions of electrons in different energy levels (K, L, M, … shells). Particles of an atom – Neutrons, protons & electrons, valency and valance electron, Atomic number, mass number, Isotopes and Isobars.

The Fundamental Unit of Life
Learn everything you need to know about the cell, through The Fundamental Unit Of Life. you will come to know about how life originates from single celled organisms.

The chapter 5, fundamental unit of life is in continuation with what the students have learnt in lower grades related to the levels of organization. The fundamental unit of life – Cell and Robert Hooke’s observation through a self-designed microscope. Furthermore, you will study structure & functions of different cells and cell membrane and Structural organization of a cell. Effect of hypotonic, isotonic & hypertonic solutions on a cell.

Tissues
It is the study of living organisms and how they interact with the environment. Biology recognizes the cell as the basic unit of life, genes as the heredity and evolution as an engine which boosts the formation of new species.

In this chapter, students will get a good grip over the topics such as the Plant Tissues such as meristematic tissue and permanent tissue. Also, some important concepts including location of meristematic tissues in plant body, various types of simple tissues, section of a stem, guard cells, etc will be learned.

Diversity in Living Organisms
You'll get excited to study of living organisms and they interact with the environment. Biology recognizes the cell as the basic unit of life, genes as the unit of heredity and evolution as an engine which boosts the formation of new species.

This chapter explains the importance of relevant groups to study the importance of various life forms. In this chapter, you will learn about the broad groups of organisms. In living organisms diversity, there are attempts made by the famous scientist, Aristotle – and Classification of animals had been done according to their living on land, water or air. Classification of organisms which you will learn in this chapter is as follows - Kingdom, Phylum, Class, Order, Family, Genus, Species and Nomenclature.

Motion
You learnt lot about energy so far. Let's dive into new topic motion where you'll understand basics of it.

In Chapter 8, Motion, you will learn about motion including motion along a straight line , types of motion like uniform motion and non-uniform motion. Crucial topics like difference between Vector & Scalar, Speed & Velocity, Distance & Displacement. Acceleration – Rate of change of velocity and average speed and velocity. Graphical representation of motion, derivation of three equation of motion and numerical based on equation of motion. Concepts on uniform circular motion.

Force and Laws of Motion
This chapter will help you to understand the concept of force and motion. This solutions given for the problems will help to build a strong foundation over which they can learn the important concepts of topics such as Balanced and Unbalanced Forces and First Law of Motion.

In this chapter, you will learn the concept of balance and unbalance forces. Starting with the First law of motion, the Galileo’s concept, law of inertia (relation of inertia to mass of the body). You will then learn the idea behind the Second law of motion – momentum, rate of change of momentum. And gradually, the Third law of motion – for every action there is equal and opposite reaction, applications on first, second and third laws of motion.

Gravitation
you learnt about the motion of objects and force as the cause of motion. Gravitation takes you further into the depths of motion of objects under the influence of gravitational force on the earth.

In Chapters 8 and 9, you must have learnt about the motion of various objects and force as the cause of that motion. Thus, you might also be aware that force is needed to change the speed or the direction of motion of any object. However, Chapter 10 of NCERT Class 9 Science CBSE takes you through the depths of motion of objects under the influence of gravitational force on the earth.

Work and Energy
"Energy" is a word that's used a lot. Here, you'll learn about how it's one of the most useful concepts in physics. Along the way, we'll talk about work, kinetic energy, potential energy, and conservation of energy.

In this chapter of NCERT Class 9 Science Textbook, you will learn about Relation between work and energy, scientific conception of work and also different forms of energy -Kinetic energy (Energy due to the motion) & Potential energy (Energy due to the position). Application of kinetic and potential energy, energy of an object at a certain height.

Sound
This chapter describes the production of Sound, Propagation of Sound. You'll come to know about Sound ECHO, reverberation, uses of multiple reflection of sound.

This chapter is a very interesting one as you will get to learn about the Reflection of Sound ECHO, reverberation, and applications of multiple reflections of sound. All these concepts are taught with by implementing various activities needed to be done in the Physics laboratory that makes the learning process more effective and interactive.

Why do We Fall ill
You'll come to know about the topic Health and its Failure including The Significance Of ‘Health’, Personal And Community Issues Both Matter For Health, Distinctions Between ‘Healthy’ And ‘Disease-Free’explains the concept of health as a state of being well enough to function well physically, mentally and socially.

In this chapter, you will understand the details of health and diseases. Health and its significance, reasons about why we fall ill and much more. Important topics like distinctions between healthy and disease free person and Personal and community issues for health are included.

Natural Resources
The chapter explains very well about importance The Breath of Life:Air. This topic is further divided into topics such as the role of the atmosphere in climate control, the movement of air:winds, rain, air pollution.

The chapter take you through the importance of the Breath of Life: Air. This topic is subdivided into topics such as the role of the atmosphere in climate control, how air moves (movement of air): winds, rain, air pollution.

Improvement in Food Resources
You comes under the Unit of Food; Food Production. This chapter will help you to learn about improvement in Crop Yields. The solution given for the problems will help to build a strong foundation in crops, their production, and protection.

This chapter explains you about Improvement in Crop Yields and other useful topics. How to make Improvement in food resources and livestock? The major groups of activities for improving crop yields –Crop production improvement, crop variety improvement, crop protection management.