A point source emits monochromatic electromagnetic waves into air uniformly in all directions. You measure the amplitude Emax of the electric field at several distances from the source. After graphing your results as Emax versus 1/r, you find that the data lie close to a straight line that has slope 75.0 N * m/C. What is the average power output of the source?

A point source emits monochromatic electromagnetic waves into air uniformly in all directions. You measure the amplitude Emax of the electric field at several distances from the source. After graphing your results as Emax versus 1/r, you find that the data lie close to a straight line that has slope 75.0 N * m/C. What is the average power output of the source?