Which graph shows the variation of magnetic susceptibility (\( \chi \)) with magnetising field (\( H \)) for a paramagnetic substance?
Show Hint
In magnetic susceptibility curves, paramagnetic substances show an increase in susceptibility with an increasing magnetic field, reaching saturation. This is best shown by graph (B).
Step 1: Understanding the behavior of magnetic susceptibility.
Magnetic susceptibility (\( \chi \)) for a paramagnetic substance typically increases as the magnetic field (\( H \)) is applied and reaches a saturation value. At higher field strengths, the susceptibility tends to level off, showing a near-constant behavior. Step 2: Analyzing the options. (A) Graph (A): This graph shows a decreasing magnetic susceptibility as the magnetic field increases, which is incorrect for a paramagnetic substance. (B) Graph (B): Correct — This graph shows the expected behavior of a paramagnetic substance where the susceptibility increases and then levels off at higher magnetic fields. (C) Graph (C): This graph shows a saturated behavior but at an inappropriate initial stage. It does not represent the typical trend for paramagnetic substances. (D) Graph (D): This graph shows an oscillating trend, which is incorrect for paramagnetic substances. Step 3: Conclusion.
The correct answer is (B), as it correctly depicts the variation of magnetic susceptibility with the applied magnetic field for a paramagnetic substance.
