Electric Fields The Electric Field Electric Fields Lines Field due to a Point Charge Field due to an Electric Dipole Field due to a Line of Charge Field due to a Charged Disk Point Charge in an Electric Field Dipole in an Electric Field pps by C Gliniewicz

When gravity was first discussed, we hardly used the term gravitational field, but one can think about how a mass knows there is a gravitational force. One can say that a “field” exists which explains a force at a distance. The same can be said or the space around an electric charge. An electric field exists around the charge. For the gravitational field For the electric field Unlike the gravitational field which always points toward the mass producing the field, electric fields point away from a positive charge and electric fields point into a negative charge. Field lines never cross. When opposite charges attract, the field lines connect the positive charge to the negative charge. When like charges are near each other, the field line do not connect the charges together. pps by C Gliniewicz

The electric field at any point is the vector sum of the electric fields due to all the charges around the point in question. An electric dipole consists of two equal and opposite charges at a constant separation. The direction of the dipole points from the positive toward the negative charge. The dipole moment is denoted by the letter, p. The distance between the charges is labeled, d. The electric field due to the dipole along the axis of the dipole (the z axis) A charge distribution consisting of a large number of closely spaced charges are said to be continuous. Charge density can be defined along a line, on a surface or throughout a volume. pps by C Gliniewicz

The electric field at some distance, r, from the line of charge is If the line of charge forms a circle, one can determine the electric field along the axis passing through the center of the circle of radius, R. At some distance z>>R, At some distance, z, along the axis of a disk with uniform charge on the surface, the electric field is The electric field at some distance from an infinite sheet of charge is When the electric field is great enough to remove the electrons from the atoms in the air, the electrons are set into motion and the atoms emit light, a spark. The is called electrical breakdown. pps by C Gliniewicz

When an electrical dipole is placed in an electric field, the dipole experiences a torque. Potential energy in a dipole can be calculated by determining the integral of the torque and angle. pps by C Gliniewicz