APPLICATION OF FARADAY’S LAW OF
COURSE NAME: ELECTRMECHANICAL ENERGY CONVERSION
COURSE CODE: EGYA 3001
INSTRUCTOR: PROFESSOR ADEL ELGAMMAL
BACHELOR OF APPLIED SCIENCE IN UTILITIES ENGINEERING
STUDENT NAME: LINLEY PILGRIM
STUDENT ID #: 50995
DATE SUBMITTED: 26th September 2018
TABLE OF CONTENTS
1.ABSTRACT12.INTRODUCTION23.ELECTRIC GUITAR34.APNEA MONITOR45.INDUCTION STOVE56.THE ELECTROMAGNTIC GUN67.CONCLUSION78.REFERENCES8TABLE OF FIGURES
Figure 1- Electromagnetic Induction in an Electric Guitar3Figure 2- Apnea Monitor4Figure 3- Electromagnet in an Induction Stove5Figure 4- Electromagnetic in a Rail Gun6-17145443230000
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The purpose of this report is to discuss the application and the importance of electromagnetic induction, which was founded by Michael Faraday when he conducted his first experiment to reveal its phenomenon. The four different applications that will be discussed will show its construction and how Faraday’s Law applies to its operating system.
The electric guitar application will show the use of a device called the “pick-up” that is used to magnetize the guitar string and as the string is plucked, a fluctuation in the magnetic field and flux creates a sound effect.
The Apnea monitor is used to monitor the breathing and heart rate of persons, mostly babies. When their breathing stops, the pattern of the induced voltages stabilizes, and external monitors will sound an alarm to alert someone that something is wrong.
Inductive stoves, as they relate to Faraday’s law, demonstrate how alternating magnetic fields are used to generate heat that is transferred through a conductive material for cooking applications.
We will also discuss electromagnetic gun. This application uses electromagnetic fields created from an electric circuit to launch a single projectile at high speeds and over great distances, without using explosives.
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Michael Faraday was on born September 22, 1791 in England and he was the English physicist and chemist who was responsible for the invention and understanding of electromagnetism. He revealed Electromagnetic Induction on August 29th in the year 1831 and continued to develop the different creations of electromagnetic induction.
He demonstrated that an electromotive force (e.m.f) produced around a closed path is directly proportional to the rate of change of the magnetic flux through any surface bounded by that path. His experiment demonstration was validated by using a coil and a wire. By passing a permanent magnet through a coil of wire swiftly, it generated a temporary current.
Faraday’s Law applications can be seen in our everyday world today even as new technology is being developed in the industry. It has become part of our everyday lives in entertainment, health and even in the military services.
In this report we will discuss Faraday’s Law as it pertains to its application the in the electric guitar, the Apnea monitor, the electric stove and the electromagnetic gun.
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3. ELECTRIC GUITAR
The electromagnetic induction principle of the electric guitar is that it transforms string vibrations into electromagnetic energy. This electric guitar has electromagnets which are used for generating an electrical signal that is rectified and amplified to reach an appropriate audible sound level.
The guitar consists of a part called the pick-up, which is responsible for picking up the sound for amplification. This pick-up consists of a number of magnets equal to the number of strings on the guitar. The equal number of magnets has a thin wire wrapped around them to make them a coil. These magnets are placed under the string and when the guitar is on, the area of the string that is above the magnet is subsequently magnetized and this magnetism produces an electrical wave that is transferred to the amplifier by means of the coil.
When the guitar strings are pulled they vibrate, which cause movement over the magnets, changing the magnetic flux through the coil and by this movement an EMF is generated in the coil and sound is produced. Figure 1 below shows the basic principle of Faraday’s law with resection to the function of the electric guitar.
Photo showing the Electromagnetic Induction in an Electric Guitar
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4. APNEA MONITOR
The Apnea monitor is a device that is used to detect the cessation of breathing in infants and adults who are at risk of respiratory failure and alert the parent or caretaker attendant.
One end of the monitor, which has a coil with an alternating current flowing through it , is attached to the person’s chest. The other end of the monitor has a pick-up coil and the magnetic flux that is generated by the current flow through the coil passes through the pick-up coil and a voltage is induced. During the person’s breathing, where there is expansion and contraction, there is a change in the surface area which subsequently causes a change in the strength of the induced voltage on the pick-up coil. In other words, as surface area changes when the person breathe, so will the induced voltage, therefore if the person has stopped breathing, the voltage remains constant or stabilizes and this will result in the monitors’ alarm to sound and alert someone that attention to the individual is required.
Figure 2 is a photo of the Apnea monitor.
Figure 2- Apnea Monitor
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5. INDUCTION STOVE
The induction stove, unlike the traditional stove, uses electricity by transferring the electrical energy by induction from a coil into ferromagnetic cookware. In the inductive stove there is an electromagnetic coil and when the stove is turned on, an alternating current flows through the coil generating a magnetic field around it and at the surface of the burner. This alternating current in the coil causes a fluctuation in the magnetic field in the burner. When ferromagnetic cookware is in contact with the burner, the magnetic field penetrates the pot causing a current flow to be induced through the base of the pot. The current that flows in the pot, resistance of the current occurs at the base of the pot causing it to heat up and thus heat is transferred to the contents in the pot. Therefore Faraday’s law of electromagnetic induction of the induction stove states that constant changes in the magnetic field produced by the alternating current in the coil will induce currents called eddy currents in the ferromagnetic cookware. The eddy currents result in the heating of the ferromagnetic cookware material and to the pots’ contents by thermal conduction.
Figure 3 shows a basic principle of the induction stove operations.
Figure 3- Electromagnet in an Inductive stove
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6. THE ELECTROMAGNTIC GUN
The electromagnetic gun, also called a rail gun, is a device that uses electromagnetic force to launch high velocity projectiles by means of a sliding armature that is accelerated along a pair of conductive rails. It is typically used as weapons which do not need explosives for their operation. The railgun is made up of a pair of parallel conductors or rails and a sliding armature which is accelerated by the electromagnetic effects of a current that flows down one rail, into the armature and then back along the other rail.
1043940344868500Its operations consist of the two metal rails parallel to each other with one being negative and the other being positive. They are both connected to a power supply and the conductive projectile is placed in between them to complete the electrical circuit. When current flows from the power supply through the negative rail, across the projectile, through the positive rail and back into the power supply, a magnetic field throughout the loop is generated around each conductor which follows the general ‘right-hand’ rule of thumb. When the current flows in opposite direction along each rail, the magnetic field between the rails is at right angles to the plane and armature and as it combines with the supplied current in the armature, resulting in a Lorentz force being generated which is responsible for the acceleration of the projectile. Lorentz force is a force which is exerted by a magnetic field on a moving electric charge.
Figure 4- Electromagnetic in a Rail Gun
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In conclusion, we have seen that current is induced in a circuit when there is movement between the coil and a permanent magnet as a result of the EMF that is produced.
Faraday’s law of Electromagnetic Induction states that whenever there is relative motion between a conductor and a magnetic field, the linkage with the flux and the coil changes and this change causes an induced voltage across the coil. This type of electromagnetic induction involves the use of a coil wire and a permanent magnet to generate this voltage. In today’s society, it is proven that Faraday’s law plays an integral part of our everyday lives as it exists in current and new technologies being developed.
The engineering industry uses the application of this law in their manufacturing process as discussed in this report as well as other applications such as transformers, DC generators and so on.
The four applications that were discussed in this report gave us a better understanding of how the law works in the construction of each component in the entertainment, health, food and military industries.
The mathematical formula for Faraday’s law is:
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Chapman, S. J. (2005). Electric machinery fundamentals. (4th ed.) United States of America, NY: McGraw-Hill.
Woodford, C. (2015, July 18). Electric guitars. Retrieved from http://www.explainthatstuff.com/electricguitars.htmlPetronzio, M. (2012, December 13). How an electric guitar actually works. Retrieved from
http://mashable.com/2012/12/13/electric-guitar/#rvcUljtq2gqYGerbis, N. (2015, September 25). How Induction Cooktops Work. Retrieved from How Stuff Works :http://home.howstuffworks.com/induction-cooktops2.htm
How an Induction Stove Works, and the Right Pans to Use. (n.d). Retrieved from http://www.thekitchn.com/why-cant-i-use-just-any-type-of-cookware-with-my- induction-stovetop-food-science-217963Allain, R. (2014, August 12). THE PHYSICS OF THE RAILGUN. Retrieved from Wire https://www.wired.com/2014/08/the-physics-of-the-railgun/
Harris, W. (2014, January 21). How Rail Guns Work. Retrieved from How Stuff Works:
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