Subject Area

Physics, Laboratory

Type of Submission



The vacuum permeability constant (also known as the magnetic constant), $\mu_0$, measures the ability of classical vacuum to transmit a magnetic field. In this experiment, we measured the permeability constant by using the relationship described by Ampere’s Law, relating the force due to a magnetic field in a region of space to the current passing through the region. In order to measure the magnetic force, we used small weights to provide a gravitational force, and found the current it took the opposing magnetic force to balance the gravitational force. A plot of the gravitational force vs. the current squared allowed us to extract $\mu_0$ as the slope.\\ According to NIST CODATA, the value of the permeability constant is $\mu_0$ = 1.257$\times$$10^{-6}$$\frac{N}{A^{2}}$. In this experiment, we determined the permeability constant to be $\mu_0$ = (1.0$\pm$0.3)$\times$$10^{-6}$$\frac{N}{A^{2}}$. Thus, the expected value of $\mu_0$ was within our measured value and its associated uncertainty.