What do you mean by magnetic flux through a surface?

Explanation

### Step-by-Step Solution:

1. **Definition of Magnetic Flux**:
Magnetic flux is defined as the total number of magnetic field lines that pass through a given surface area. It quantifies the amount of magnetic field passing through that surface.

2. **Mathematical Expression**:
The magnetic flux (Φ) through a surface can be mathematically expressed as:
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