One can not align the apparatus to eliminate entirely the effects of the Earth's magnetic field. Consider the case where electrons having accelerated through 28.0 V then enter the uniform field region between the Helmholtz coils. With the coil current set to zero, the electron beam was observed to have a slight curvature due to the earth's magnetic field. The current in the coil had to be set to 0.512 A to set the electron beam exactly straight. If each coil has 62 turns and has a mean radius of 66.0 cm, calculate the component of the earth magnetic field perpendicular to the entering electron beam: