Introduction to Electrical and Electronics Engineering PDF

INTRODUCTION TO ELECTRICAL AND ELECTRONICS ENGINEERING COURSE CODE: 23EEE104 Course Overview  3 Credit course L-T-P-C: 3-0-0-3  Course objective:  To impart basic knowledge of electrical quantities and provide working knowledge for the analysis of DC and AC...

INTRODUCTION TO ELECTRICAL AND ELECTRONICS ENGINEERING COURSE CODE: 23EEE104 Course Overview  3 Credit course L-T-P-C: 3-0-0-3  Course objective:  To impart basic knowledge of electrical quantities and provide working knowledge for the analysis of DC and AC circuits.  Understand the characteristics and applications of diode and transistors.  To facilitate understanding of thyristors and operational amplifier circuits.  Course Outcomes: ◼ CO1: Ability to understand basic electric and magnetic circuits. ◼ CO2: Ability to analyze dc and ac circuits. ◼ CO3: Ability to understand basic principles of pn junctions and transistors. ◼ CO4: Ability to analyze basic transistor and op-amp based circuits. CO-PO Mapping Syllabus Textbooks Evaluation Pattern Internal External Total Components Weightage Components Weightage Mid Term Exam 30% Internal + End semester exam 50% 50% External=100 Continuous evaluation 20% Continuous Evaluation Class test (2 nos.) : 10 marks Tutorial (2 nos.) : 10 marks INTRODUCTION TO ELECTRICAL AND ELECTRONICS ENGINEERING LECTURE NO: 1 BASIC CONCEPT Structure of an Atom Concept of charge  In all the atoms, there exists number of electrons which are very loosely bound to its nucleus.  When such electrons are removed from an atom it becomes positively charged.  This is because of loosing negatively charged particles i.e. electrons from it.  As against this, if excess electrons are added to the atom it becomes negatively charged.  Thus total deficiency or addition of excess electrons in an atom is called its charge and the element is said to be charged.  The following table shows the different particles and charge possessed by them. Particle Charge possessed in Coulomb Nature Neutron 0 Neutral Proton 1.602 X 10-19 Positive Electron 1.602 X 10-19 Negative  The following points should be noted about electric charge:  The coulomb is a large unit for charges. In 1 C of charge, there are 1/(1.602 × 10-19) =6.24×1018 electrons.  According to experimental observations, the only charges that occur in nature are integral multiples of the electronic charge, e = −1.602 × 10-19 C.  The law of conservation of charge states that charge can neither be created nor destroyed, only transferred. Key points  1 coulomb = charge on 6.24 X 10 18 electrons.  If an element has a positive charge of one coulomb then that element has a deficiency of 6.24 X 1018 electrons.  Addition or removal of electrons causes the change in the nature of charge possessed by the element.  When a conducting wire (consisting of several atoms) is connected to a battery (a source of electromotive force), the charges are compelled to move; positive charges move in one direction while negative charges move in the opposite direction.  This motion of charges creates electric current.  An electrical effort required to drift free electrons in one particular direction, in a conductor is called Electromotive force (e.m.f).  It is denoted as E and measured in volts. Relation between Charge and Current  Electric current is the time rate of change of charge, measured in amperes (A).  Mathematically, the relationship between current i, charge Q, and time t is 1 ampere = 1 Coulomb/second Ans:  How much charge is represented by 4600 electrons?  Electric Potential and Potential Difference  When two similarly charged particles are brought together, they try to repel each other while dissimilar charges try to attract each other.  This means, every charged particle has a tendency to do work.  This ability of the charged particle to do the work is called its electric potential.  The unit of electric potential is volt.  In electric circuits, flow of current is always from higher electric potential to lower electric potential.  The difference between the electric potentials at any two given points in a circuit is known as Potential Difference (p.d).  This is also called voltage between the two points and measured in volts.  The symbol for voltage is V.  Electrical Power and Energy  When a direct current of I amperes is flowing in an electric circuit and the voltage across the circuit is V volts, then Power in watts, P = V I  Although the unit of energy is the joule, when dealing with large amounts of energy, the unit used is the kilowatt hour (kWh). Ans: Question  You have two types of lamps: an LED lamp and a CFL lamp. Both lamps are rated to provide the same level of brightness, but they have different power ratings. The LED lamp has a power rating of 10 watts (W). The CFL lamp has a power rating of 15 watts (W).  You use each lamp for 5 hours per day. Calculate the energy consumed by each lamp in one day and one month (assuming 30 days in a month). Additionally, compare the energy cost if the electricity rate is 6 rupees per kilowatt-hour (kWh).