Abstract

We explain, after 190 years to the knowledge of the author, the mechanism that creates longitudinal forces, using the Biot-Savart-Grassmann-Lorentz force law, which are found to be in complete agreement with the longitudinal forces predicted by the Ampère force law. We have also shown that a straight wire squared off at one end and pointed at the other can move in a mercury trough in the direction of the current flow by using both the Biot-Savart-Grassmann-Lorentz (B-S-G-L) and Ampère force laws. The direction of its motion is opposite to that of the pointed end. In addition we have found that the theoretically calculated velocity of the “submarine”, by using both the B-S-G-L and Ampère force laws, is in complete agreement, within the error, with the one experimentally measured by the experimenters. Therefore, it has been shown that the B-S-G-L force law can anticipate longitudinal forces, which is the only aspect that distinguished these two force laws, and, thus, now, both laws are in all aspects equivalent.