  We present the first survey of electric field data using the ARTEMIS
spacecraft in the solar wind to study inertial range turbulence. It was found
that the average perpendicular spectral index of the electric field depends on
the frame of measurement. In the spacecraft frame it is -5/3, which matches the
magnetic field due to the large solar wind speed in Lorentz transformation. In
the mean solar wind frame, the electric field is primarily due to the
perpendicular velocity fluctuations and has a spectral index slightly shallower
than -3/2, which is close to the scaling of the velocity. These results are an
independent confirmation of the difference in scaling between the velocity and
magnetic field, which is not currently well understood. The spectral index of
the compressive fluctuations was also measured and found to be close to -5/3,
suggesting that they are not only passive to the velocity but may also interact
nonlinearly with the magnetic field.
