What is magnetic flux ? Write its SI unit. Explain its relation with magnetic field lines using diagram.

Explanation

### Step-by-Step Solution:

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

**Step 2: Mathematical Expression**
Magnetic flux is mathematically expressed as the dot product of the magnetic field (B) and the area vector (A) of the surface through which the field lines pass. The formula for magnetic flux is given by:
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