Concept:Magnetic flux is the product of magnetic field and area. To find its fundamental derived SI unit, we combine the constituent equations.
Formula:$$ \Phi = B \cdot A = \left( \frac{F}{IL} \right) \cdot A $$
Solution:- Start with the formula substituting standard units: \( \text{Wb} = \text{Tesla} \cdot \text{m}^2 \).
- Expand Tesla using the force law: \( \text{T} = \frac{\text{N}}{\text{A \cdot m}} \).
- Multiply by area (\( \text{m}^2 \)): \( \Phi = \left( \frac{\text{N}}{\text{A \cdot m}} \right) \cdot \text{m}^2 \).
- Simplify the meters: \( \frac{\text{N \cdot m}}{\text{A}} = \text{N A}^{-1} \text{m} \).
Why other options are incorrect:Option B is the unit for the magnetic field (Tesla) itself. Options C is an incorrect dimension. Option D is specifically the unit of magnetic field strength, not flux.
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