The dimensional formula for the permittivity of free space (ε₀) can be derived from the equation for the electrostatic force, given by Coulomb's law: F = 1/(4π ε₀) · (q₁q₂/r²). In this equation, F represents force, q₁ and q₂ are charges, and r is the distance between the charges.
Breaking Down the Units
To find the dimensional formula for ε₀, we start with the dimensions of the other quantities involved:
- Force (F): [M L T⁻²]
- Charge (q): [A T]
- Distance (r): [L]
Setting Up the Equation
From the equation, we can rearrange it to isolate ε₀:
ε₀ = 1/(4π) · (q₁q₂)/(F · r²)
Substituting Dimensions
Now, substituting the dimensions into the equation:
ε₀ = (A² T²) / ([M L T⁻²] · [L²])
Calculating the Result
This simplifies to:
ε₀ = (A² T²) / ([M L³ T⁻²]) = [M⁻¹ L⁻³ T⁴ A²]
Final Answer
Thus, the correct dimensional formula for the permittivity of free space ε₀ is:
B. [M⁻¹ L⁻³ T⁴ A²]