Class 12th Physics-Electric Charges and Fields- Type of Charges – Positive and Negative part-3
Here’s a clear and student-friendly explanation of Class 12th Physics – Chapter: Electric Charges and Fields, focusing on “Types of Charges – Positive and Negative” (Part-3). Perfect for CBSE, NEET, and state board students.
Contents
- 1 Electric Charges – Part 3: Types of Charges (Positive and Negative)
 - 2 Types of Charges
 - 3 How are Charges Produced?
 - 4 Like Charges and Unlike Charges
 - 5 Important Points
 - 6 Real-Life Examples
 - 7 Diagram Idea (You can draw for notes)
 - 8 Tip for Exams:
 - 9  For Practice:
- 9.1 Class 12th Physics-Electric Charges and Fields- Type of Charges – Positive and Negative part-3
 - 9.2 I Exercise – II Electric Charges And Fields – Question Bank
 - 9.3 Revision Notes for Class 12 Physics Chapter 1 – Electric …
 - 9.4 Chapter 1 Electric Charge; Coulomb’s Law
 - 9.5 Chapter Three – CURRENT ELECTRICITY
 - 9.6 ELECTRIC CHARGES AND FIELDS
 
 
  Electric Charges – Part 3: Types of Charges (Positive and Negative)
  What is Electric Charge?
Electric charge is a fundamental property of matter responsible for electric force interactions. It comes in two types:
  Types of Charges
| Type of Charge | Symbol | Examples | 
|---|---|---|
| Positive | + | 
Protons, glass rubbed with silk | 
| Negative | – | 
Electrons, ebonite rubbed with fur | 
  How are Charges Produced?
Charges are produced by friction, conduction, or induction.
Example:
- When a glass rod is rubbed with silk, the glass rod loses electrons → becomes positively charged.
 - When an ebonite rod is rubbed with fur, the ebonite gains electrons → becomes negatively charged.
 
  Like Charges and Unlike Charges
| Interaction | Behavior | 
|---|---|
| Like charges | Repel each other (e.g., + vs + or – vs –) | 
| Unlike charges | Attract each other (e.g., + vs –) | 
Bring a charged plastic comb near tiny paper pieces – they get attracted due to charge interaction.
  Important Points
- Charge is quantized: q=±neq = \pm ne, where e=1.6×10−19 Ce = 1.6 \times 10^{-19} \, C
 - Charge is conserved: It can neither be created nor destroyed.
 - Charge is transferable: By rubbing or contact.
 - Charges reside on the surface of conductors.
 
  Real-Life Examples
| Situation | Charge Involved | 
|---|---|
| Lightning | Negative charge builds in clouds | 
| Static electricity | Rubbing clothes, combing hair | 
| Photocopier machine | Uses static charges to attract toner | 
  Diagram Idea (You can draw for notes)
Glass Rod (+)         Silk Cloth (–)
    ↓                         ↓
Loses electrons       Gains electrons
Ebonite Rod (–)        Fur (+)
    ↓                         ↓
Gains electrons       Loses electrons
  Tip for Exams:
“Charge is always conserved and quantized” – always include this in theory answers. 
Use proper SI units: Charge (Coulombs), Elementary Charge (e). 
  For Practice:
- Q1: What happens when a positively charged object touches a neutral object?
 - Q2: Why does a charged balloon stick to a wall?
 
Would you like:
- A short summary PDF?
 - Numerical problems from this topic?
 - A video explanation or animations?
 
Let me know what format helps you best!