A sheet of relative permeability 100 is placed inside the solenoid, so as to fill the space. What will be the energy stored inside the solenoid?

Explanation

To find the energy stored inside the solenoid when a sheet of relative permeability 100 is placed inside, we can follow these steps:

### Step 1: Understand the formula for magnetic energy density
The magnetic energy density (u) inside a solenoid is given by the formula:
\[ u = \frac{B^2}{2\mu} \]
where \( B \) is the magnetic field inside the solenoid, and \( \mu \) is the magnetic permeability of the material inside the solenoid.
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