รายงานการวิจัย -- มหาวิทยาลัยเทคโนโลยีราชมงคลพระนคร, 2553The experimental models of electric fields were set up by using 4 forms of electric poles, a point - point, point - rod, parallel rod and coaxial ring. The equipotential lines and
electric line of force were drawn by using Microsoft Office Visio Program 2007. The drawing of equipotential lines and electric field had shown the direction of electric field moving from the positive electrode toward the negative electrode and perpendicular to the equipotential line. The point - point poles in 10 cm. distance have constant and the highest electric fields which is 28.64 V/m. The electric fields of point - rod, parallel rod and coaxial ring are 60.51 V/m, 45.81 V/m and 181.98 V/m respectively.Rajamangala University of Technology Phra Nakho
