Final answer:
Using magnetic or electrically interactive materials in the Cavendish experiment would likely measure electromagnetic properties such as electric permittivity or magnetic permeability rather than gravitational constants.
Step-by-step explanation:
If the Cavendish experiment were performed using materials that interact magnetically or electrically, the results would not yield the gravitational constant but might instead measure electromagnetic interactions, such as the magnetic or electric force between the materials. This could inadvertently measure properties like electric permittivity or magnetic permeability, depending on the specifics of the materials and their arrangements.
Maxwell's equations show the relationship between electric permittivity, magnetic permeability, and the speed of light. The electric permittivity (Essential Knowledge 1.E.4) and the magnetic permeability (Essential Knowledge 1.E.5) are critical concepts in understanding electromagnetic phenomena, as they describe how electric and magnetic fields propagate through different materials and space.
While the Cavendish experiment aims to investigate gravitational interactions and laws, utilizing magnetic or electrically interactive materials could interfere with this aim and create a different set of experimental outcomes. This error would provide insights into electromagnetic rather than gravitational properties. Such results would be significant but would constitute a different type of experiment altogether than the Cavendish experiment designed to measure gravitational forces.