All educational material on the website has been prepared by the best teachers having more than 20 years of teaching experience in various schools. These notes have the solution of numerical problems, solved exercise short questions and easy wording theory all in one pdf. Notes on alternating current class 12 page 01 alternating current a. Lesson 7 alternating current alternating current as we have seen earlier a rotating coil in a magnetic field, induces an alternating emf and hence an alternating current. In 1886, ganz works, an electric company located in budapest, electrified all of rome with ac. Certain sources of electricity most notably, rotary electromechanical generators naturally produce voltages alternating in polarity, reversing positive and negative over time.
Note again that the voltage and current are not in phase. Learn about the different concepts of alternating current only at byjus. May 26, 2019 in alternating current circuit, the ratio of emf applied and consequent current produced is called the impedance and is denoted by z, i. Rms value, average value, peak factor and form factor of half wave rectified alternating current. Iit jee handwritten notes pdf for class 11 and class12 physics jee notes of alternating current. Why, alternating current and direct current, of course. The frequency of an alternated circuit is measured by the number of times the. In fact there are certain types of works for which alternating current is unsuitable and, therefore, direct current is absolutely necessary such as for electroplating, charging of storage batteries, refining of copper, refining of aluminium, electrotyping, production of. Jun, 2018 these notes have the solution of numerical problems, solved exercise short questions and easy wording theory all in one pdf. Cbse notes class 12 physics current electricity aglasem. Home up board question papers ncert solutions cbse papers cbse notes ncert books motivational.
Alternating series test we have the following test for such alternating series. Figure 1 shows the plot of alternating voltage and alternating current as a function of time in a circuit that has only a resistor and a source of alternating current an ac generator. Alternating current, ac is generally used for power distribution, which is why the mains sockets in our homes and at work provide an alternating current to. The direction of current will be clockwise and anticlockwise and it will. It can be represented as, the currents and voltages in a. C is the current that changes in magnitude direction continuously with respect to time. The best app for cbse students now provides alternating current class 12 notes latest chapter wise notes for quick preparation of cbse board exams and schoolbased annual examinations. Alternating current 235 george westinghouse 1846 1914 george westinghouse 1846 1914 a leading proponent of the use of alternating current over direct current. Answers of assignment are given at the end of each assignment with complete solutions. Half wave rectified alternating current is one whose onehalf cycle has been suppressed i. Home iit books download download allen physics chapter wise notes and problems with solutions. Electromagnetic induction and alternating current class 12. Download cbse class 12th revision notes for chapter 7 alternating current in pdf format for free. Jul 02, 2019 alternating current class 12 notes chapter 7.
This conversion of ac into dc is accomplished through the use of a commutator. It is crucial to note that the maximum amplitude of the ac voltage source is not equal to the sum of the maximum voltage amplitudes across the three circuit. I we see from the graph that because the values of b n are decreasing, the. Aug 19, 2019 unsubscribe from physics wallah alakh pandey. Class 12 physics revision notes for chapter 7 alternating current. Class 12 physics current electricity get here the notes for class 12 physics current electricity. Pdfdownload iit jee handwritten notes physics jeemain. Candidates who are pursuing in class 12 are advised to revise the notes from this post. State the differences between ac and dc voltage and current. Class 12 physics chapter 7 alternating current notes pdf download alternating current ac is the current generated by the vast majority of power plants and used by most power distribution systems, as it is cheaper to generate and has fewer energy losses than direct current when transmitting electricity over long distances. Alternating current circuits and electromagnetic waves. Chapter 31 alternating current phasors and alternating currents resistance and reactance magneticfield energy the lrc series circuit power in alternatingcurrent circuits resonance in alternatingcurrent circuits transformers. Basic concepts of alternating current cedengineering.
Single phase ac circuits definition of alternating quantity an alternating quantity changes continuously in magnitude and alternates in direction at regular intervals of time. This is possible only when you have the best cbse class 12 physics study material and a smart preparation plan. Cbse ncert notes class 12 physics alternating current. Rms values since voltage and current are always changing we need some way of averaging out their effect. Figure shows the plots of the current and voltage as a function of time for the inductor. The rms value is also called effective value of an a. Determine the rms value of the current in the circuit.
Cbse class 12 physics notes alternating current cbse and ncert students can refer to the attached file. Download allen kota physics chapterwise notes and problems with solutions all jee mainsadvance study materials available to download for free. Class 12 physics notes chapter 7 alternating current pdf. In case of ac the current is changing its magnitude at every instant of time. The value of current will oscillate between a maximum value and a minimum value. In a simple circuit that is used to light a bulb with a battery, the battery provides direct currenta current flowing in only one direction. Alternating current vs direct current as useful and as easy to understand as dc is, it is not the only kind of electricity in use.
With the help of notes, candidates can plan their strategy for particular weaker section of the subject and study hard. The rms value of alternating current is defined as that value of the steady current, which when passed through a resistor for a given time, will generate the same amount of heat as generated by an alternating current when passed through the same resistor for the same time. Mar 05, 2019 class 12 physics notes chapter 7 alternating current. Alternating current, ac and direct current, dc both have their advantages and disadvantages, but this means that there is a choice to select the best option for any given use or application. Lowpitch notes such as those produced by a tuba or bassoon consist of air molecule vibrations that are relatively slow low frequency. Magnetic flux through a surface of area a placed in a uniform magnetic field b is defined as cos.
Electromagnetic induction and alternating current class 12 pdf do. Electric charge in alternating current ac, on the other hand, changes direction. Dec 24, 2019 candidates who are pursuing in class 12 are advised to revise the notes from this post. A current which flows first in one direction in a circuit, called the positive direction, then in the reverse direction or negative direction is called alternating current. An ac generator is a conducting coil rotating in a magnetic field. Class 12 important questions physics chapter 7 alternating current. Due to this reason the rms value of current is also known as effective or virtual value of current. Cbse class 12 physics notes alternating current concepts.
Westinghouse was convinced that the technology of alternating current was the key to the. Class 12 physics notes chapter 7 alternating current pdf download free. As it will be shown later, alternators operate with both alternating ac and directcurrent dc electric power. The rms value of alternating current can also be defined as the direct current which produces the same heating effect in a given resistor in a given time as is produced by the given a. Class 12 physics notes chapter 7 alternating current cbse class 12 physics notes pdf. This article is concerned with the analysis of simple direct current circuits of two types. In fact, the i or rms current is the equivalent dc current that would produce the same average power loss as the alternating current. Alternating current class 12 notes physics mycbseguide. Fundamentals of alternating current electrical engineering. Download revision notes for alternating current class 12 notes and score high in exams.
Get pdf download of class 12 physics chapter 7 alternating current class 12 notes, video lectures and more made by expert teachers of vidyakul to score high marks in your exams. The dc can be considered a particular case of the general ac, with frequency equal to zero. It will help you to revise the whole chapter within the span of one hour and score good marks in class 11 and 12 and specially in competitive exams like jee mains and jee advanced. Magnetic flux magnetic flux through an area in a magnetic field is defined as a magnetic field is visualized by drawing lines of field, which are imaginary. Download cbse notes, neet notes, engineering notes, mba notes and a lot more from our website and app. Notes for alternating current circuit chapter of class 12 physics. Alternating current class 12 notes chapter 7 learn cbse. Important terms associated with an alternating quantity are defined below. Figure 1 current and voltage from an ac source through a simple resistor. In particular, if a coil rotates in the presence of a magnetic field, the induced emf varies sinusoidally with time and leads to an alternating current ac, and provides a source of ac. So, go ahead and check the important notes for class 12 physics alternating currents. Alternating current is defined as the current that varies like a sine function with time. Class 12 chap 7 alternating current 01 ii ac dc current.
Both ac and dc describe types of current flow in a circuit. Note that your fingers point in the direction that the north. However, it is possible to convert the alternating current that is induced into the armature into a form of direct current. Where did the australian rock band acdc get their name from.
Candidates who are ambitious to qualify the class 12 with good score can check this article for notes. Cbse notes for class 12 physics alternating current provide a detailed insight into the topic. The rms value of alternating current is defined as that value of the steady current, which when passed through a resistor. Fundamentals of alternating current 3 figure 121 sinusoidal wave values. Class 12 physics notes chapter 7 alternating current pdf cbse. Ohms law yields v c ix c, where v c is the rms voltage across the capacitor and i is the rms current in the circuit consider a circuit with only an inductor and an ac generator. Thomas edison, on the other hand, had constructed 121 dc power stations in the united states by 1887. Alternating current ac it is the current which varies in both magnitude as well as direction alternatively and periodically. Electromagnetic induction and alternating current revision notes. Learn more problems of rms voltage, peak current, total power, source frequency by ncert at byju. These are the alternating current class 12 notes prepared by team of expert teachers. Electromagnetic induction and alternating current class 12 pdf download. Alternatingcurrent circuits summary physics libretexts. Notes for electromagnetic induction chapter of class 12 physics.
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