Question

What is the SI unit of electric flux?

Hint:

Electric flux unit can be quickly remembered as: \[ \text{Electric field} \times \text{Area} \] So just multiply the unit of \(E\) by \(m^2\).

Answer 1

Concept:
Electric flux (\(\Phi_E\)) is defined as the surface integral of the electric field over a surface: \[ \Phi_E = \vec{E} \cdot \vec{A} \] From Gauss’s Law: \[ \Phi_E = \frac{Q}{\varepsilon_0} \] Thus, the unit of electric flux can be determined from either definition.
Step 1:
The SI unit of electric field \(E\) is: \[ \text{N/C} \quad \text{or} \quad \text{V/m} \]
Step 2:
The SI unit of area \(A\) is: \[ \text{m}^2 \]
Step 3:
Therefore, electric flux unit: \[ (\text{V/m}) \times (\text{m}^2) = \text{V·m} \] Alternatively, \[ (\text{N/C}) \times (\text{m}^2) = \text{N·m}^2/\text{C} \] Both forms are equivalent SI units.