Review Test 1


  1. If a Cu2+ ion drops through a potential difference of 12 V, what kinetic energy will it acquire (in the absence of friction)?
  2. The absolute potential at the center of a square is 3 V when a charge of +Q is located at one of the square's corners. What is the absolute potential at the square's center when a second charge of -Q is placed at one of the remaining corners?
  3. The plates of a parallel-plate capacitor are maintained with constant voltage by a battery as they are pulled apart. During this process, the amount of charge on the plates must
    1. increase
    2. decrease.
    3. remain constant.
    4. either increase or decrease. No way to tell from the information given.
  4. A dielectric material such as paper is placed between the plates of a capacitor holding a fixed charge. What happens to the electric field between the plates?
    1. No change.
    2. Becomes stronger.
    3. Becomes weaker.
    4. Reduces to zero.
  5. A parallel-plate capacitor is connected to a battery and becomes fully charged. The capacitor is then disconnected, and the separation between the plates is increased in such a way that no charge leaks off. The energy stored in this capacitor has
    1. increased.
    2. decreased.
    3. not changed.
    4. become zero.
  6. Doubling the voltage across a given capacitor causes the energy stored in that capacitor to
    1. quadruple
    2. double
    3. reduce to one half
    4. reduce to one fourth
  7. The resistance of a wire is defined as
    1. (length) (resistivity)/(cross-sectional area).
    2. (current) / (voltage).
    3. (voltage) / (current).
    4. none of the above.
  8. If the resistance in a constant voltage circuit is doubled, the power dissipated by that circuit will
    1. increase by a factor of two.
    2. increase by a factor of four.
    3. decrease to one-half its original value.
    4. decrease to one-fourth its original value.
  9. As more resistors are added in series to a constant voltage source, the power supplied by the source
    1. increases
    2. decreases
    3. does not change.
    4. increases for a time and then starts to decrease.
  10. As more resistors are added in parallel to a constant voltage source, the power supplied by the source
    1. increases.
    2. decreases.
    3. does not change.
    4. increases for a time and then starts to decrease.
  11. When resistors are connected in parallel, we can be certain that
    1. the same current flows in each one.
    2. the potential difference across each is the same.
    3. the power dissipated in each is the same.
    4. their equivalent resistance is greater than the resistance of any one of the individual resistances.
  12. A resistor and a capacitor are connected in series to an ideal battery of constant terminal voltage. When this system reaches its steady-state, the voltage across the resistor is
    1. greater than the battery's terminal voltage.
    2. less than the battery's terminal voltage, but greater than zero.
    3. equal to the battery's terminal voltage.
    4. zero.
  13. Three identical capacitors are connected in series to a battery. If a total charge of Q flows from the battery, how much charge does each capacitor carry?
  14. Sphere A carries a net charge and sphere B is neutral. They are placed near each other on an insulated table. Which statement best describes the electrostatic force between them?
    1. There is no force between them since one is neutral.
    2. There is a force of repulsion between them.
    3. There is a force of attraction between them.
    4. The force is attractive if A is charged positively and repulsive if A is charged negatively.
  15. The net work done in moving an electron from point A at -50 V to point B at +50 V along the semi-circular path shown is

  16. It takes 10 J of energy to move 2 C of charge from point A to point B. What is the potential difference between points A and B?
  17. What is the force between a 1.5 micro-C charge and a 2.5 micro-C charge which are 15 cm apart?
  18. Two 1 C charges have a force between them of 1 N. How far apart are they?
  19. A 110 V hairdryer is rated at 1200 W. What current will it draw?
  20. Three identical resistors are connected in parallel to a 12-V battery. What is the voltage of any one of the resistors?
  21. A 3-ohm resistor is connected in parallel with a 6-ohm resistor. This combination is connected in series with a 4- ohm resistor. The resistors are connected to a 12-volt battery. How much power is dissipated in the 3-ohm resistor?