EDUCATION CENTRE

 Basic properties of electric charge   There are three basic properties of electric charge :- Additivity :- The total charge of system is the algebraic sum of all the individual charges located at different points inside the system.                        q 1, q 2, ......., q n  Quantization :- Electric charge comes in fixed, tiny units (like electrons) and can't be divided into smaller amounts. It's like counting individual particles, not a continuous flow. Conservation :- The total electric charge in a closed system remains constant over time. Charge can't be created or destroyed, only transferred from one object to another. Examples: 1 . Chemical reactions : Charge is conserved in chemical reactions. 2 . Particle interactions : Charge is conserved in particle collisions and decays.

 Electrostatic Induction  When a charged object is brought near a neutral object, it makes the neutral object temporarily charged without touching it. How it works: 1. A charged object is brought near a neutral object. 2. The charged object induces a redistribution of electrons in the neutral object. 3. The neutral object becomes polarized, with one side having an opposite charge to the charged object. Examples:- 1. Lightning Rods: Attract lightning due to electrostatic induction. 2. Electrostatic Precipitators: Remove dust particles from air. 3. Induction Charging: Charging objects without direct contact.

 Conductors  The substances through which electric charge can flow easily. They contain a large number of free electrons easily.  Example :-  => Metals, Human, acid, graphite, etc. Insulators The substances through which electric charge cannot flow easily. Due to the absence of free electron. Example :- => Wood, Diamond, Plastic, etc,

 ELECTRONIC THEORY OF FRICTIONAL ELECTRICITY 1.  Two objects rub together 2.  Electrons move from one object to another 3.  One object becomes positively charged (loses electrons) 4.  The other becomes negatively charged (gains electrons)

Electrostatics  Electrostatics is the study of electric charges at rest. Example: Balloon and Hair Experiment 1 . Rub a balloon on your hair (create friction). 2. Bring the balloon near a wall. What happens ? The balloon sticks to the wall ! Why ? When you rub the balloon on your hair, it builds up static electricity (negative charge). This charge attracts the wall's particles, making the balloon stick. Simple Explanation: Static electricity is a "magic" force that attracts or repels objects when they have an electric charge. In this case, the static charge helps the balloon stick to the wall. Applications of Electrostatics. These are applications of electrostatics: 1. Electrostatic Loudspeakers 2. Paint and Powder Coating 3. Fly Ash Collection 4. Xerox Machines 5. Cathode-Ray Tubes (TVs, Radar)

   Electricity Charge  Electric charge is a fundamental property of matter that causes it to experience a force when placed in an electric field. Electric charge is scalar quantity.  Its SI unit is Coulomb ( C ). There are two types of Electric Charge  1. Positive charge (+) 2. Negative charge (-)  [Note: Electron and proton have two charges but neutrons has no charge because, It is an electrically neutron subatomic particle. There is equal number of electrons and protons presence inside it. ]

 Friction electricity  When two materials rub against each other, electrons can transfer from one material to another, creating static electricity. Examples: 1. Rubbing a balloon on hair 2. Walking on carpet and getting shocked This phenomenon is used in various applications, including: 1. Static electricity generators 2. Air purification systems

Introduction Everything is all our surrounding  is matter. Matter has scientific name of materials.      Example :- Pen, pencil, Human, etc. Every thing is made up of matter. Matter is made of very small particles.

NCERT solutions for class 9th  science chapter 1,  Matter in Our Surroundings