Which term is defined as the permittivity of free space?

Which term is defined as the permittivity of free space?

• A. Permittivity of free space
• B. Permeability of free space
• C. Electrical conductivity of air
• D. Electrical resistance of vacuum

Answer: (A)

The concept here is how electric fields exist in empty space. The permittivity of free space, usually denoted ε0, is a fundamental constant that describes the baseline ability of vacuum to permit electric fields. It sets the strength of the electric interaction in vacuum, appearing in Coulomb’s law as the factor that determines the force between point charges: the force scales with 1/(4π ε0). It also shows up in Maxwell’s equations and is linked to the speed of light through the relationship c^2 = 1/(μ0 ε0), with μ0 being the magnetic counterpart, the permeability of free space. The numerical value is about 8.854 × 10^-12 farads per meter, a small constant that defines how electric fields propagate in empty space. When a dielectric is placed between charges, the effective permittivity becomes ε = ε0 εr, increasing capacitance and reducing the field inside the dielectric. So the term that names the property of empty space itself and is defined as the permittivity of free space is the constant ε0. The other options refer to different properties—magnetic permeability, air’s conductivity, or vacuum resistance—and do not describe electric field behavior in vacuum in the same way.

The concept here is how electric fields exist in empty space. The permittivity of free space, usually denoted ε0, is a fundamental constant that describes the baseline ability of vacuum to permit electric fields. It sets the strength of the electric interaction in vacuum, appearing in Coulomb’s law as the factor that determines the force between point charges: the force scales with 1/(4π ε0). It also shows up in Maxwell’s equations and is linked to the speed of light through the relationship c^2 = 1/(μ0 ε0), with μ0 being the magnetic counterpart, the permeability of free space.

The numerical value is about 8.854 × 10^-12 farads per meter, a small constant that defines how electric fields propagate in empty space. When a dielectric is placed between charges, the effective permittivity becomes ε = ε0 εr, increasing capacitance and reducing the field inside the dielectric.

So the term that names the property of empty space itself and is defined as the permittivity of free space is the constant ε0. The other options refer to different properties—magnetic permeability, air’s conductivity, or vacuum resistance—and do not describe electric field behavior in vacuum in the same way.