NCERT Exemplar Solutions for Class 12 Physics Chapter 4

About NCERT Exemplar Solutions for Class 12 Physics Chapter 4 – Moving Charges and Magnetism

The fourth chapter of Class 12 Physics, Moving Charges and Magnetism, explores the intimate connection between electricity and magnetism. After learning about electrostatics and current in earlier chapters, students are introduced to the magnetic effects produced by moving charges. This chapter is vital as it lays the groundwork for electromagnetic theory and also explains the functioning of many practical devices such as electric motors, galvanometers, and cyclotrons. The NCERT Exemplar Solutions for this chapter provide a clear and methodical approach to problem-solving, ensuring that students develop strong conceptual and analytical skills. The chapter begins with Oersted’s discovery, which showed that a current-carrying conductor produces a magnetic field around it. The Exemplar problems help students visualize this relationship and calculate magnetic field strength using the Biot–Savart law. Through carefully explained solutions, learners understand how to determine the field at different points due to current elements, straight conductors, circular loops, and solenoids.

Another significant concept in this chapter is Ampere’s Circuital Law, which simplifies the calculation of magnetic fields in situations involving symmetry. The NCERT Exemplar Solutions include a variety of problems that test students’ ability to apply this law to solenoids, toroids, and other current distributions. These problems encourage logical thinking and help in building a strong base for more advanced topics in electromagnetism. The chapter also emphasizes the motion of charged particles in a magnetic field. Students learn how a magnetic field exerts a force on moving charges, leading to circular or helical paths. The Exemplar Solutions provide step-by-step approaches to solving numerical questions based on the magnetic force, radius of circular motion, frequency of revolution, and the principle of cyclotrons. Such problems are particularly useful for competitive exams where precision and speed are essential. Force on a current-carrying conductor and torque on a current loop in a uniform magnetic field are also covered in detail. These ideas form the basis for understanding the working of electric meters and motors. The NCERT Exemplar Solutions highlight practical applications through numerical and conceptual questions that connect theory with real-world usage. Towards the end, the chapter discusses the concept of a moving coil galvanometer. The Exemplar problems provide insight into its principle, working, and conversion into ammeter and voltmeter, which is important from both board examination and practical laboratory perspectives.

In conclusion, the NCERT Exemplar Solutions for Moving Charges and Magnetism give students the tools to master one of the most fascinating aspects of physics. By practicing these problems, learners strengthen their problem-solving skills, improve conceptual clarity, and gain the confidence to apply theoretical knowledge to real-life and examination scenarios. This chapter not only enriches understanding but also prepares students for higher studies in physics and engineering.