http://www.ck12.org Chapter 17. Electric Fields
CHAPTER
17 Electric Fields
Chapter Outline
17.1 The Electric Field
17.2 THEELECTRICPOTENTIAL IN AUNIFORMFIELD
17.3 MILLIKANOILDROPEXPERIMENT
17.4 THECAPACITOR
17.5 REFERENCES
When two objects are electrically charged, they exert a force on each other. If the objects have like charges, they
repel; if they have opposite charges, they attract. The child above has become negatively charged after his ride down
the slide. Since each of his individual strands of hair is negatively charged, they repel each other. The force of the
attraction or repulsion between charges can be calculated using Coulomb’s law. On some occasions, however, it is
difficult to identify and/or quantify one of the charges involved. To work with such a situation, physicists consider
what is called an electric field. These fields exist in the area around charged particles and exert forces on all charges
within the field. By using the field for calculations, we need not know anything about the charge itself.