Question

If the given figure shows the relation between magnetic field (B along y-axis) and magnetic intensity (H along x-axis) of a ferromagnetic material, then the point that represents coercivity of the material is:

• A. \( \text{P} \)
• B. \( \text{Q} \)
• C. \( \text{R} \)
• D. \( \text{S} \)

Hint:

In a hysteresis loop, coercivity corresponds to the point where the curve intersects the \( H \)-axis when the magnetic field is reversed and \( B = 0 \).

Answer 1

The Correct Option is C

Step 1: Understanding the hysteresis curve
A hysteresis loop shows the relationship between magnetic induction \( B \) and magnetic field intensity \( H \) for a ferromagnetic material. Step 2: Definition of coercivity
Coercivity is the value of \( H \) at which the magnetic induction \( B = 0 \). This occurs when the material is completely demagnetized after saturation. Step 3: From the figure
In the figure, point \( R \) is the point on the H-axis where \( B = 0 \) while traversing the loop in reverse. Hence, \( R \) represents the coercivity of the material.