THE UNIVERSITY OF TRINIDAD
THE UNIVERSITY OF TRINIDAD & TOBAGO
THE UNIVERSITY OF TRINIDAD & TOBAGO
B.A.S.c Utilities Engineering
Electromechanical Energy Conversion
REPORT #1
APPLICATIONS OF FARADAY’S LAW OF ELECTROMAGNETIC INDUCTION
Student Name: Rebekah Paulsingh
Student ID#: 67061
Table of Contents
1.Abstract………………………………………………………………………………….3
2.Introduction……………………………………………………………………………..4
3.Theoretical Background………………………….…………………………………….5
4.Analysis and Technical Discussion…………………………………………………….6
4.1Electric guitar………………………………………………………………………. ….6
4.2Apnea Monitor………………………………………………………………………… 7
4.3Induction stove……………………………………………………………………….…8
4.4Electromagnetic gun……………………………………………………………………9
5.Conclusion………………………………………………………………………………10
6.References………………………………………………………………………………11
ABSTRACT
In this report labelled, “Applications of Faraday’s law of electromagnetic induction,” the author delves into the numerous ways in which electromagnetic induction is utilised in electric guitars to form sound, for a secure and more competent way of cooking in an induction stove, to surveil infants’ cardiorespiratory problems via apnea monitors and to accelerate objects at high speeds in electromagnetic guns. These functions are established on the principle that a coil conducting a.c. yields an electromotive force, emf, which activates a current into a nearby conductor.
INTRODUCTION
In the current generation we live in that is rapidly evolving of note is that dependence and accompaniment electricity and magnetism share with each other. Electric and magnetic field exist everywhere. In recognition of Michael Faraday and his law of electromagnetic induction the contribution to today’s society which now are dependent and heavily relient has also sought to improve efficiency. In lieu of this, the report intends to invetigate Faraday’s Law of electromagnetic induction in the following applications;
Electric Guitar
Apnea Monitor
Induction Stove
Electromagnetic Gun
The objective of this report is;
To comprehend the construction of different devices and how Faraday’s Law of electromagnetic induction is justified in them.
THEORTICAL BACKGROUND
Faraday’s Law of Induction states that the EMF induced in a circuit is directly proportional to the time rate of change of magnetic flux through the circuit. This can be represented by the formula;
EMF=-Nd?dt.
Lorentz force is the force exerted on a charged particle q moving with velocity v through magnetic field B. The entire electromagnetic force F on the charged particle is called the Lorentz force (after the Dutch physicist Hendrik A. Lorentz) and is given by;
F=q×v×Bq×v=IL?F=I×L×BWhere,
I: current (Amp)
L: length (m)
ANALYSIS AND TECHNICAL DISCUSSION
Applications of Faraday’s law of electromagnetic induction
Electric Guitar
The electric guitar consists of six small magnets with six respective metallic strings hovering above the magnets. A copper coil of hundreds or thousands of turns is wounded around the magnets. This construct is known as the pickup of the guitar. The strings are magnetized by the magnetic field created by the magnets. 1 Thus, when the strings are plucked while playing the instrument they become magnetized due to the pickup attached to the body of the guitar in proximity to the strings. Also, due to the strings being plucked, this creates changes to magnetic flux through the coil/pickup, which in accordance to Faraday’s Law of electromagnetism, produces an induced EMF in the pickup coil. Hence, the induced emf acts as an electrical signal (A.C signals) which is amplified to the audible range on a speaker. Hence there is no current detected at the leads when the strings are in a static position.
Apnea Monitor
This monitor is a device used to analyse infants with heart and breathing rate problems. It includes of an alternating current carrying coil which is adjusted in proximity to the chest of the infant called the apnea belt which is connected to the apnea monitor as shown above. The alternating currents produces an electromagnetic field that is picked up by the detection coil. 2 When there is a change in breathing pattern or high/low rate, this indicates fluctuation in the magnetic field linkage with the pickup coil which leads to an induced emf in the coil. If the infant’s heart rate slows down or stops breathing, this induced emf creates an alert alarm to indicate that the infant has a respective problem and needs immediate medical care providers attention.
Induction Stove
The induction stove converts electrical energy into heat energy. This consists of a flat coil that is connected to an a.c. power supply and an insulative material surface such as ceramic placed on top of the coil. 3 In this stove, there is a high frequency current which is a result of using various electronic devices that generates high temperatures. This is how Faraday’s law of alternating current moves in two directions creating change in magnetic field or changing flux takes place. When a vessel/pot, specifically a ferromagnetic one is placed on the ceramic stove, the magnetic field of the high frequency alternating current creates electromagnetic induction that gets linked with the base of the vessel. Hence, inducing current in it. These currents when circulating in nature creates a heating effect known as eddy’s current. These eddy’s current produces heat which leads to better cooking of the food in the vessel. Also, this current is more effective and efficient than a conventional stove. It is noted that only vessels/pots made from ferrous material can work on induction stove.
Electromagnetic Gun
The electromagnetic gun also known as the rail gun that consists of two conductors or rods parallel to each other and a conductive projectile which bridges the gap between the two conductors. 4 This gun can be taken as a parallel wire set, one carrying the current from source and the other one taking it back to the source. The direction of current in both the wires is opposite. The magnetic field in the area between the two conductors comes out to be additive in nature and hence a larger force can be exerted on the bullet. Note, the conductors are connected to a power supply; one connected to the positive terminal and the other to the negative terminal. The bullet must pass over these conducting lines which carries a current itself. As, we know that a current carrying conductor when placed in magnetic field experiences a force. When the current flows, it goes up one of the conductors, then across the projectile and finally down the other conductor. Due to Faraday’s law, a magnetic field is produced around the conductors and projectile. It is known that the bullet (current carrying conductor) will experience a force due to the magnetic field lines which converges in the gap creating an inward, repulsion force between both conductors (Lorentz force). This force produces bullet to be shot out. The amount of force produced depends on the length of the conductors, the amount of current and the size of the magnetic field,
F=l×I×B.
CONCLUSION
In this report, we see electromagnetic induction principles takes place in various applications and how it was introduction in different ways by disturbing the natural flow of the magnetic field, a changing flux is created thus, current is induced into a nearby conductor.
REFFERNCES
1Chris. Woodford. (2017, June, 23). Electric guitar Online.Available email: http://www.explainthatstuff.com/electricguitars.html2 Unknown Author. (2014, Summer). The Applications of Faraday’s Law Online.Available email: https://www.coursehero.com/file/p9hh0v/Applications-of-Faradays-Law-Apnea-Monitor-The-coil-of-wire-attached-to-the/3Unknown Author. (Unknown date). How an Induction Cooktop Works Online.Available email: http://www.finecooking.com/article/how-an-induction-cooktop-works4Rhett. Allain. (2014, August, 12). The Physics of the Railgun Online.Available email: https://www.wired.com/2014/08/the-physics-of-the-railgun/
