Articles - ELECTRICAL CLASSROOM

How do Fuel Cells Work?

Fuel cells cleanly and efficiently convert chemical energy from hydrogen-rich fuels into electrical power and usable high-quality heat in an electrochemical process that is virtually absent of pollutants. What are fuel cells? Fuel cells are non-polluting energy resources. It cleanly and efficiently converts chemical energy from hydrogen-rich fuels into electrical power. Each fuel cell consists … Read more

Difference between mico processors and micro controllers

Microprocessor It has many support devices like ROM, Read-Write memory, Serial interface, Timer, I/O ports etc. All these support devices are interfaced to microprocessor via a system bus. All support devices in a microprocessor based system are external. The system bus is composed of an address bus, data bus and control bus. Microcontroller All the support … Read more

How does a car Air Conditioner work?

Air conditioning works continuously and has refrigerant continually circulating around a sealed system. Most automotive A/C systems are made up of six main components:-

Compressor and mounting brackets
Condenser
Receiver/ drier
Expansion Valve
Evaporator
Hose & fittings

The easiest way to explain how the system works is to trace the refrigerant as it flows through the system:-

Speaker is a device which converts electrical signal into sound waves. By
its property, sound is made when an object makes the particles around it
vibrate. These vibrations travel through the air, and reach our ears. Our brain
interprets this motion as sound. The amplitude of the waves corresponds to the volume level we hear and the frequency decides the nature of sound.

Scanners are used to create a soft copy of available photos and documents.

When we open the scanner we can see a glass plate. We have to place the
document that we need to scan over the glass plate.

Optical Mouse

The Optical mouse was introduced by Agilent Technologies in 1999. In this technology uses a tiny camera that takes thousands of pictures per second to determine position and speed. A very small light emitting diode is used in the optical mouse. Commonly preferred LED is red LED. The light from the LED falls on the mouse pad or desk surface and bounces back onto a CMOS (Complimentary Metal Oxide Semiconductor).

Fluorescent lamps

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Fluorescent lamps are commonly used every where. These lamps are more energy efficient than ordinary incandescent light bulbs.

081209 light bulb 03- ELECTRICAL CLASSROOM

In an incandescent light bulb, light is produced by the heating of filament. It has a carbon-based filament in the center of the bulb connected to the two terminals and maintained at vacuum glass chamber. This filament has a high resistance to electric current.

Operation of generators

The generator is a device which converts the mechanical energy into electrical energy.

Construction

In order to understand the operation of a simple generator, consider rectangular coil ABCD placed in a magnetic field as shown in the figure. The two ends of the coil are connected to the two copper half rings (or split rings) R₁ and R₂ called commutator. There are two carbon brushes B₁ and B₂ which press lightly against the two half rings.