Electric Current

Terms & Objectives


The Indiana Physics Standards that Relate to Chapter 34 - Electric Current are:

New Terms:

potential difference

electric current


voltage source

electromotive force (emf)



Ohm's Law

direct current

alternating current



drift velocity (speed)

electric power


When you finish your study of electric current you should be able to:

  1. Tell what electric current is, and the units in which it is commonly measured. (34.2)
  2. Describe the conditions necessary for current to flow. (34.1)
  3. Given a diagram of a bulb, wire, and a battery, tell whether the bulb will be lit. (34.1)
  4. Name some common voltage sources. (34.3)
  5. Recognize electromotive force as a synonym for voltage. (34.3)
  6. Tell what resistance is and what units are used to measure it, and describe the factors that affect resistance. (34.4)
  7. Describe the relationship between current, resistance and voltage in a simple circuit. (34.5)
  8. State Ohm's Law and tell what each of the symbols mean. (34.5)
  9. Solve simple numerical problems involving: (34.5)
    1. Voltage (potential difference)
    2. Current
    3. Resistance
  10. Describe how an electric shock affects the human body. (34.6)
  11. Discuss ways to avoid electric shock. (34.6)
  12. Discuss emergency procedures in case of electric shock.
  13. Describe the difference between DC and AC voltage and current. (34.7)
  14. Tell whether household current is AC or DC and know the nominal voltage and frequency. (34.7)
  15. Tell what a diode does in an electric circuit. (34.8)
  16. Describe how AC can be converted to DC. (34.8)
  17. Describe the motion of electrons in a DC or an AC circuit, and discuss how energy is transported in a DC or an AC circuit. (34.9)
  18. Tell where the electrons in an electric circuit originate.(34.10)
  19. Recognize that electric power equals current times voltage. (34.11)
  20. Solve simple numerical problems involving: (34.11)
    1. Power
    2. Current
    3. Voltage
    4. Resistance
  21. Determine the cost to run an appliance given: (34.11)
    1. Power consumption of the appliance
    2. Time
    3. Energy cost per kilowatt hour
  22. Recognize the watt second and kilowatt hour as units of energy. (34.11) 

Common Misconceptions to Correct:

In the study of electric current, it is very common for beginning physicists to have the following misconceptions - do you? If so, you need to put in some extra effort to discover why they are incorrect, and correct them!

last update April 3, 2008 by JL Stanbrough