5.23 A sample of paramagnetic salt contains 2.0 * 10²⁴ atomic dipoles each of dipole moment 1.5 * 10^–23 J T^–1. The sample is placed under a homogeneous magnetic field of 0.64 T, and cooled to a temperature of 4.2 K. The degree of magnetic saturation achieved is equal to 15%. What is the total dipole moment of the sample for a magnetic field of 0.98 T and a temperature of 2.8 K? (Assume Curie's law)

There are various important topics in the physics chapter 5 class 12 magnetism and matter. These topics are important for both cases, conceptual and numerical questions. Read below:

• Magnetism 
• Bar Magnet as an Electromagnet
• Magnetic Field Due to Magnetic Dipoles
• Type of Magnetic Materials: Ferromag

In JEE Main exam, it is a significant chapter. There can be 6 to 8 questions from this chapter, a weightage of nearly 6.6%.

The exact weightage varies from year to year. This chapter comes under a broader category which can be "Magnetism" or "Modern Physics". In NEET exam, the chapter's weightage is low to moderate and there can be 6-7% of questions from this chapter.

The chapter is one of the small and easy chapter of class 12 Physics. It includes - properties of magnetic materials, magnetic dipoles, and Earth's magnetic field.

When the electric charges moves, it creates attraction or repulsion. It creates magnetic forces and fields and called magnetism. The term "magnetism and matter" talks about the way magnetic forces and matter interact.