NCERT Books Free Download for Class 12 Physics Chapter 7 - Alternating Current

The topics included in the chapter are:

7.1- Introduction 

7.2- AC Voltage Applied to a Resistor

7.3- Representation of AC Current and Voltage by Rotating Vectors — Phasors

7.4- AC Voltage Applied to an Inductor

7.5- AC Voltage Applied to a Capacitor

7.6- AC Voltage Applied to a Series LCR Circuit

7.7- Power in AC Circuit: The Power Factor

7.8- LC Oscillations

7.9- Transformers
 

List of Sample Questions

• Section 7.2- 1 Question

• Section 7.4- 1 Question

• Section 7.5- 3 Question

• Section 7.6- 1 Question

• Section 7.7- 4 Question

• Section 7.8- 1 Question

• Exercise in end- 11 questions

• Additional Exercise: 10 questions
  
  

About NCERT

Established in the year 1961 The National Council of Educational Research and Training (NCERT) is an autonomous organization, which focuses mainly on providing qualitative education in primary and secondary levels of the education system.

• It deals with the preparation and publication of textbooks, study materials in form of newsletters, journals and multimedia digital materials.

• Apart from providing material, it deals with developing and spreading of innovative ideas regarding teaching techniques and aids in providing training to newly appointed staff.

• It as an organization collaborates with state educational institutions, various universities and non-governmental organizations working in the field of imparting education.

• NCERT acts as a nodal, for achieving the goal of basic elementary education, apart from the state education system.

• NCERT not only plays an important role in the Indian education system but also maintains its cultural relationships with other countries and facilitates the foreign exchange of students.
  
  

Preparing the Chapter

Here you can read Chapter 7 of the Class 12 Physics NCERT Book. Also after the chapter, you can get links to Class 12 Physics Notes, NCERT Solutions, Important Question, Practice Papers etc. Scroll down for Alternating Current from NCERT Book Class 12 Physics Book & important study material.

It is easy to download the NCERT Class 12 Books. Just click on the link, a new window will open containing all the NCERT Book Class 12 Physics pdf files chapter-wise. Select the chapter you wish to download and it's done. You will have the PDF on your device to study offline.

The chapter alternating current teaches about electric current, which periodically changes its magnitude and reverses its direction with time unlike Direct Current (DC), which flows only in one direction. In the Alternating Current Class 12 NCERT Solutions, students learn the basics of current that varies like a sine function with time as its value oscillates between the maximum and minimum.

This alternating current class 12 broadly explains how electric energy is transformed into AC, which can be controlled by a transformer. This makes an easy flow of power through the power lines even at high voltage.

Important Bullet Points For The Chapter:

• Alternating current is the current that varies as a sine function with time. As we know the value of the sine function has the range of -1 to 1 the same goes for the value of current that oscillates between the maximum and minimum value.

• Unlike Direct current the value of Alternating current changes with time. The direction of current is both clockwise and anticlockwise and keeps on periodically occurring.

• The frequency of the Alternating Current depends directly on the electron's movement and the changes in the direction of the electron’s movement.

• AC current is generated due to AC voltage.

• Alternating current comes into action when a magnet that is in motion is concerned instead of a steady magnet. 

Alternating current is an important chapter in Class 12 physics, this chapter along with Electromagnetic Induction contributes to 17 marks in the total. which is around a quarter of the total and hence is a very important chapter. In the previous few years consistently there have been two questions from this chapter in JEE Mains and hence contributes to 6.6 % in the total mark distribution.