Introduction
Electricity is one the most important sources of energy in the world. Almost every electronic device in every household depends on electricity. As such, mobile phones, computers, refrigerators, heaters, and bulbs and other major house appliances rely on electricity (Bloomfield 399). Electricity is a secondary source of energy. This source of energy has several primary sources, which includes water, oil, geothermal, nuclear, coal, and wind. The principle of electricity depends on the flow of electric charges (Bloomfield 362). Flowing electric charges are referred to as electric current.
Magnetism can be generated from electricity application (Bloomfield 351). The source of magnetism is current and magnetic moments. When electric current flows in a conductor, it creates a magnetic field. The relationship between the two is called electromagnetism. This term refers to the generation of magnetism due to electric current. Similarly, magnetic field leads to the generation of electric current when a conductor cuts the magnetic field. To date, several individuals have assisted in the discovery and usage of electricity and magnetism. These include Maxwell, Ampere, and Faraday (Parker 56). Thomas Edison made a major contribution when he invented light bulbs.
AC generators and motors
Most of the machines operate with the aid of motors and generators (Bloomfield 374). Their roles can be interchanged, a motor can be used as a generator, and a generator can work as a motor. Motors are devices that convert electrical energy to mechanical energy, while the generator converts kinetic energy into electrical energy. This is the case in industrial applications. Conveyor belts, rollers, and grinding machines utilize the rotating power from a motor. Generators are used in areas where there is no electricity (Bloomfield 388). Generators use sources of fuel such as diesel and oil to produce electricity. The generated electricity can be used as a source of energy or used as a backup source. During generation of electricity, magnetism plays a great role in generators. With respect to AC motors, current is supplied to the windings leading to a production of a torque on the windings. Torque is simply a rotating force, which is required to drive various shafts in machines for their operation. Given that AC current is used, the motor spins at the same rate of recurrence with the sine wave. The term is referred to as synchronous motors. However, these motors are not commonly used and this leaves room for the use of induction motors. Induction motor coils are supplied with current indirectly as opposed to the case of synchronous motors. The current is induced in the coils with the help of magnetism (Bloomfield 382). An AC motor consists of commutators, brushes, coils, and permanent magnets. The magnetic field is generated around the Stator coils and the magnetic field experiences counter force from the magnetic field of permanent magnets. This in turn rotates the shafts of the machines for their operation.
AC generators consist of two permanent magnet coils and brushes. The coils are placed in between the two permanent magnets. The mechanical energy is supplied to the coils. Thereafter, the turning of a coil in a magnetic field generates emfs at both sides of the coil. The two emfs are constructive leading to a sinusoidal voltage. This technical explanation is in accordance with Faraday’s law. The rotation of the coils causes changes in the magnetic flux in the coils hence generating voltage.
Magnetic recording
In the computing world, storage of information is very important (Bloomfield 392). The safety of the stored information is of concern. Memory space required for storage of information should be considered when choosing the method of storage. Magnetic storage involves the storage of information on a magnetic medium. The major magnetic storage medium is the hard disk drive. It is used for storage of both video and audio information. Other magnetic storage mediums include magnetic stripes, magnetic tapes, and floppy disks (Bloomfield 392). The operation of the analog magnetic recording utilizes both electricity and magnetism. Initially, the recording magnetic tapes are empty and in demagnetized state. The writing heads are supplied with an energy, which is relative to the information being recorded. Thereafter, the tape is made to rotate at a constant speed. The combination of the two leads to the magnetization of the tape, hence the recording takes place. When information has been stored, it can be accessed via redheads. The operations of magnetic recording require the use of electric current on the read and write heads to create magnetization on the magnetic medium for storage.
Conclusion
In conclusion, it should be noted that electricity is one the most important sources of energy in the world. The evidence of the presence of electricity is seen in phenomena such as lightning, radio waves, electromagnetic radiation, and static charges. Almost all technologies and mechanisms used in the operation of most devices utilize both electricity and magnetism. Applications range from generators, motors, relays, refrigerators and magnetic tapes. As such, electricity and magnetism plays a great role in human life.
Works Cited
Bloomfield, Louis. How everything works: making physics out of the ordinary. Hoboken: Wiley, 2007. Print.
Parker, Steve. Electricity and magnetism. Milwaukee, Wis.: Gareth Stevens Pub., 2007. Print.