Physics Topic: Electric Fields

  1. recall and use Coulomb’s law in the form F = (1/4πε0) Q1Q2/r2 for the electric force between two point charges in free space or air

  2. recall and use E = (1/4πε0) Q/r2 for the electric field strength due to a point charge, in free space or air, to solve problems

  3. define electric potential at a point as the work done per unit charge by an external force in bringing a small positive test charge from infinity to that point

  4. use the equation V = (1/4πε0) Q/r for the electric potential in the field due to a point charge, in free space or air

  5. show an understanding that the electric potential energy of a system of two point charges is U = (1/4πε0) Qq/r

  6. recall that electric field strength at a point is equal to the negative potential gradient at that point and use this to solve problems

  7. calculate the field strength of the uniform electric field between charged parallel plates in terms of the potential difference and plate separation

  8. calculate the force on a charge in a uniform electric field

  9. describe the effect of a uniform electric field on the motion of a charged particle

  10. define capacitance as the ratio of the charge stored to the potential difference and use C = Q / V to solve problems

  11. recall that the electric potential energy stored in a capacitor is given by the area under the graph of
    potential difference against charge stored, and use this and the equations U = 1/2 QV = 1/2 Q2/C = 1/2 C V2 to solve problems.