​​​​​​​Electricity and Magnetism

Electricity and magnetism are closely related phenomena that together form the field of electromagnetism. They explain how electric charges and magnetic forces interact in the physical world.

⚡ 1. Electricity

Electricity is the movement of electric charges (usually electrons) through a material, typically a conductor like copper.

🔎 Key Concepts:

• Electric Charge:

  • Two types: positive (+) and negative (−)

  • Like charges repel; opposite charges attract

• Current (I):

  • Flow of electric charge

  • Measured in amperes (A)

• Voltage (V):

  • The force that pushes the charges (like pressure)

  • Measured in volts (V)

• Resistance (R):

  • Opposition to the flow of current

  • Measured in ohms (Ω)

📘 Ohm’s Law:

V=I×RV = I \times R

(Voltage = Current × Resistance)

🧠 Examples:

• Batteries power devices

• Electricity flows in home circuits

• Light bulbs glow when current flows

🧲 2. Magnetism

Magnetism is the force produced by moving electric charges or natural magnetic materials like iron.

🔎 Key Concepts:

• Magnetic Poles:

  • Every magnet has a north (N) and south (S) pole

  • Like poles repel, opposite poles attract

• Magnetic Field:

  • The invisible area around a magnet where magnetic force is felt

  • Represented by lines going from N to S

• Earth’s Magnetic Field:

  • Acts like a giant bar magnet

  • Helps compasses point north

🧠 Examples:

• Fridge magnets

• Compass navigation

• Magnetic locks

🔄 3. Electromagnetism

When electric current flows, it creates a magnetic field. This is the principle of electromagnetism.

📘 Applications:

• Electromagnets: Coiled wires that act as magnets when current flows

• Electric motors: Convert electrical energy into motion

• Generators: Convert motion into electricity

• Transformers: Change voltage levels in power lines

🧠 Summary Table

✅ Final Thoughts:

• Electricity powers most of our technology

• Magnetism helps in motors, compasses, and data storage

• Together, they explain everything from how your phone works to how power plants generate electricity.

Understanding electricity and magnetism is essential for fields like physics, engineering, electronics, and renewable energy.