Therefore, by equating the magnitudes of the forces i.e. The unit vector r has a magnitude of 1 and points along the axis as the charges. Suppose $q_4$ is at equilibrium and Let $q_1=q_3=-5\,{\rm \mu C}$ then what is the magnitude of the charge $q_2$ and the sign of the ratio of $\frac {q_2}{q_4}$. The procedure to use the Coulombs law calculator is as follows: Step 1: Enter the charge of first, second body, distance between two bodies and x for the unknown in the respective input fields. Thus, there is no space between them to balance a test charge. Using Coulomb's lateral earth pressure theory. ' Elastic Potential Energy Calculator. }); Problem (9): Two point charges $q_1=+2\,{\rm \mu C}$ and $q_2=+8\,{\rm \mu C}$ are $30\,{\rm cm}$ apart from each other. Found inside – Page 58Assume this solution is placed into a 1 liter, spherical container. (a) Using only Coulomb's law, calculate the repulsive force on a sodium ion sitting ... window.jQuery || document.write('