Planck impedance

The Planck impedance is the unit of electrical resistance, denoted by Z_P, in the system of natural units known as Planck units.

$Z_P = \frac{V_P}{I_P} = \frac{1}{4 \pi \epsilon_0 c} = \frac{\mu_0 c}{4 \pi} = \frac{Z_0}{4 \pi} =$ 29.9792458 Ω

where

• $V_P$ is the Planck voltage
• $I_P$ is the Planck current
• $c$ is the speed of light in a vacuum
• $\epsilon_0$ is the permittivity of free space
• $\mu_0$ is the permeability of free space
• $Z_0$ is the impedance of free space

See also

• Natural units
• Planck's constant