An ac generator equipped with a device called a commutator can produce direct current. After completing this chapter you should be able to. Alternating current causes a continuing muscle contraction, often preventing people from releasing their grip on the currents source. In a simple circuit, the current is found by dividing the voltage by the resistance. Ac circuit analysis has a more general motivation and application.
Write the general equation for a sinusoidal signal based on its amplitude. The movement of an electron in the current flow is opposite to electric current. Because the voltage and current reach their maximum values at the same time, they are in phase. May 10, 2020 alternating current ac refers to systems in which the source voltage varies periodically, particularly sinusoidally. Unlike dc the flow of electric charge changes direction.
Rms values since voltage and current are always changing we need some way of averaging out their effect. Direct current is a bit easier to understand than alternating current. Jan 22, 2020 free pdf download of cbse physics multiple choice questions for class 12 with answers chapter 7 alternating current. Here the flow of electric charge happens only in one direction.
Aug 19, 2019 8 videos play all 12 chap 7 ii alternating current jeeneet physics wallah alakh pandey travel inside a black hole duration. Cbse class 12 physics chapter 7 alternating current notes in pdf are available for free download in mycbseguide mobile app. Class 12 physics revision notes for chapter 7 alternating. Alternating current 235 george westinghouse 1846 1914 george westinghouse 1846 1914 a leading proponent of the use of alternating current over direct current. Practice questions for alternating current linked comprehensive type a circuit consists of a capacitor of x c 30 ohm, a noninductive resistor of 44 ohm and a coil of inductive resistance 90 ohm and resistance 36 ohm in series is connected to 200 v,60 hz ac circuit. Pdf download cengage physics all modules top10trendings. If the primary coil draws a current of 5a and the secondary supplies a current of 90a, then the efficiency of the transformer is 1.
A stepdown transformer is employed to reduce the main supply of ac from 220v to 11v. Practice questions for alternating current for jee main. This flow of electrons in a closed circuit is called current. On the basis of the direction of movement of electrons in a closed circuit, the. 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. Electromagnetic induction and alternating current class 12 pdf do. Get yout free demo lectures in hindi, dont waste the time. Rather than oscillating back and forth, dc provides a constant voltage or current. Alternating current refers to currents and voltages which are harmonic functions. It is strictly according to the latest revised cbse syllabi and examination pattern.
Alternating current ac physics and radioelectronics. Alternating current is an electric current in which the flow of electrons or charge carriers always reverses its direction many times a second at regular intervals forward and alternating current course no. Ohms law yields v l ix l, where v l is the rms voltage across the inductor and i is the rms in the inductor resistorinductorcapacitor circuit. Download cbse class 12th revision notes for chapter 7 alternating current in pdf format for free. Notes on alternating current class 12 page 01 alternating current a. Electromagnetic induction and alternating current class 12.
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. The voltage source of an ac system puts out a voltage that is calculated from the time, the peak voltage, and the angular frequency. Alternating current class 12 notes physics mycbseguide. All chapter 7 alternating current exercises questions with solutions to help you to revise complete syllabus and boost your score more in examinations. Alternating current is more dangerous than direct current. Alternating current notes for class 12 with free pdf. Physics mcqs for class 12 chapter wise with answers pdf download was prepared based on latest exam pattern. Newtons laws of motion allen physics particle kinematics allen physics practical physics allen physics rotational motion allen physics temperature scales allen physics wave theory allen physics work energy allen physics this website is created solely for jee aspirants to download pdf, ebooks, study materials for free. Alternating current lecture 1 cbse class 12 physics chapter. The effective resistance is called the inductive reactance x l defined by x l 2. To register online physics tuitions on to clear your doubts from our expert teachers and solve the problems easily to score more marks in your cbse board exams.
Students can solve ncert class 12 physics alternating current mcqs pdf with answers to know their preparation level. Thus, he came into conflict with thomas alva edison, an advocate of direct current. Free pdf download of cbse physics multiple choice questions for class 12 with answers chapter 7 alternating current. Alternating current causes a continuing muscle contraction, often preventing people from releasing their grip on. Free pdf download of physics class 12 chapter 7 alternating current formulas prepared by expert teachers at.
Class 12 physics chapter 7 alternating current notes pdf download. Alternating current important questions with solutions for. It can be represented as, the currents and voltages in a. Fundamentals of alternating current in this chapter, we lead you through a study of the mathematics and physics of alternating current ac circuits. Magnetic flux through a surface of area a placed in a uniform magnetic field b is defined as cos. V, i maximum potential difference current voltage current amplitude.
Ncert solutions for class 12 physics chapter 7 alternating current exercises are given below to use it online or download in pdf form free for new academic session 202021. Sc part 2 physics notes for the chapter 16 having the solution to exercise short questions. Westinghouse was convinced that the technology of alternating current was the key to the. Determine the rms value of the current in the circuit. C through a solution, the motion of the positive and negative ions become vibratory. Download revision notes for alternating current class 12 notes and score high in exams. Cbse class 12 physics chapter 7 notes alternating current. These are the alternating current class 12 notes prepared by team of expert teachers. Physics mcqs for class 12 with answers chapter 7 alternating. Free pdf download of ncert solutions for class 12 physics chapter 7 alternating current solved by expert teachers as per ncert cbse textbook guidelines. Here is the direct link to learn alternating current at embibe the main difference between alternating current ac and direct current dc is that in ac, there is a constant change in the magnitude of current with respect to time but while in the dc the current remains the same with respect to time. Class 12 physics notes chapter 7 alternating current.
Ncert solutions for class 12 physics chapter 7 alternating. In direct current, the charges electrons in a metal always have a net average velocity in the same direction, leading to a current flow, although the magnitude of the current may vary with time. In alternating current circuit, the ratio of emf applied and consequent current produced is called the impedance and is denoted by z, i. Use of a device called a rectifier that converts ac to dc. Chapter ac alternating current circuits page 2 ac1 inductors and inductance in essential physics chapter 20, generating electricity, we discussed faradays law and lenzs law, and explored the tendency of a coil of wire to oppose changes in the magnetic flux passing through the coil.
Ncert solutions for class 12 physics chapter 7 pdf. So that is the reason electrolysis does not happen in a. 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. 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. Alternating current ac can behave very differently to direct current dc, depending on the circuit. Notes for alternating current circuit chapter of class 12 physics. Mar 05, 2019 class 12 physics notes chapter 7 alternating current. C is the current that changes in magnitude direction continuously with respect to time. Class 12 chap 7 alternating current 01 ii ac dc current. Ohms law and the previous expressions for power are valid for this circuit if the root mean square rms of the voltage and the rms of the current, sometimes called the effective value, are used. 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. Direct current tends to cause a single muscle contraction often strong enough to force the person away from the currents source. In fact, the i or rms current is the equivalent dc current that would produce the same average power loss as the alternating current.
1339 1023 146 183 262 850 1349 576 997 19 1552 277 851 682 1464 892 700 621 398 435 887 877 1526 163 835 794 1447 1314 841 301 688 1274 466 689 101 561 1368 260 578 649 1055 1127