Define the magnetic moment of a bar magnet. What is its direction?

Explanation

**Step-by-Step Solution:**

1. **Definition of Magnetic Moment**:
The magnetic moment of a bar magnet is a vector quantity that characterizes the magnet's strength and orientation in a magnetic field. It is defined as the torque (τ) experienced by the magnet when placed in an external magnetic field (B). Mathematically, it can be expressed as:
\[ \mu = \frac{\tau}{B} \]
where:
...