A rod is inserted as the core in the current-carrying solenoid of the previous problem. (a) What is the magnetic intensity `H` at the centre? (b) If the magnetization `I` of the core is found to be `0.12 A m^(-1)`, find the susceptibility of the material of the rod. (c) Is the material paramagnetic, diamagnetic or ferromagnetic?

Explanation

To solve the problem step by step, we will address each part of the question systematically.

### Step 1: Determine the Magnetic Intensity `H` at the Center
From the previous problem, we know that the magnetic intensity `H` at the center of the solenoid is unaffected by the presence of the rod. Therefore, we can directly use the value provided.

**Solution:**
The magnetic intensity `H` at the center of the solenoid is given as:
\[ H = 1500 \, \text{A/m} \]
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