Class 12th Physics-Electric Charges and Fields- Type of Charges – Positive and Negative part-3
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 [hide]
- 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 –) |
Example Activity:
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!