Utilization of Electrical Energy

Key applications of electrical energy in industries, homes, and transportation.

⚡ Illumination

Illumination is the application of electrical energy to provide visible light.
Units: Lumen (lm), Lux (lm/m²), Candle power.
Types of lighting: Incandescent, Fluorescent, LED, Mercury vapor lamps.
Laws: Inverse square law and Lambert's cosine law.
Applications: Homes, streets, industries, hospitals, stadiums.

🔥 Electric Heating

Electric heating is the process of converting electric energy into heat energy.
Types: Resistance heating (oven, heater), Induction heating, Dielectric heating.
Advantages: Clean, fast, precise control, high efficiency.
Applications: Cooking, water heating, industrial furnaces.

🔧 Electric Welding

Welding by means of heat generated from electric current.
Types: Arc welding (AC/DC), Resistance welding (spot, seam).
Applications: Metal fabrication, automobile, shipbuilding, construction.

🔋 Electroplating

Electrochemical process of depositing a metal layer using electric current.
Purpose: Corrosion resistance, decoration, surface finish.
Setup: DC power supply, electrolyte solution, anode (metal), cathode (object).
Applications: Jewelry, hardware, electronics, automotive parts.

🚗 Electric Drives & Motors

Electric drive: System using electric motors to drive machinery.
Advantages: Smooth control, easy automation, less maintenance.
Motors used: DC motors, Induction motors, Synchronous motors, Universal motors.
Applications: Fans, pumps, trains, cranes, elevators, electric vehicles.

📘 Previous Year Questions

Q: What is the unit of illumination?
Ans: Lux (lm/m²).
Q: Name two methods of electric heating.
Ans: Resistance heating and Induction heating.
Q: Why is DC used in electroplating?
Ans: DC ensures unidirectional ion flow for proper metal deposition.