A closely wound solenoid of 800 turns and area of cross section `2*5xx10^-4m^2` carries a current of `3*0A`. Explain the sense in which the solenoid acts like a bar magnet. What is its associated magnetic moment?

Explanation

To solve the problem, we will break it down into two parts: explaining how the solenoid acts like a bar magnet and calculating its associated magnetic moment.

### Step 1: Understanding how the solenoid acts like a bar magnet
A solenoid is a coil of wire that generates a magnetic field when an electric current passes through it. When the current flows through the solenoid, it creates a magnetic field similar to that of a bar magnet.

- The end of the solenoid where the current exits behaves like a north pole, while the end where the current enters behaves like a south pole.
- The magnetic field lines inside the solenoid are parallel and close together, indicating a strong and uniform magnetic field, similar to the magnetic field of a bar magnet.

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