The amplitude of the magnetic field of an electromagnetic wave propagating in vacuum is 7.9 μT. What is the average energy density (in μJ/m3) of the electric field of this electromagnetic wave? (1 point ; Content Area #5)

Place several e-field sensors at a few points on different equipotential lines, and look at the relationship between the electric field and the equipotential lines. which statement is true? 1-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of higher voltages. 2-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of lower voltages. 3-at any point, the electric field is parallel to the equipotential line at that point.