DC Fundamentals Unit 6 – Ohm's Law
Unit 6 – Ohm's Law .....................................................................................................................
UNIT OBJECTIVE
At the completion of this unit, you will be able to demonstrate the relationship of resistance,
current, and voltage by using Ohm's law.
UNIT FUNDAMENTALS
Electric potential difference is expressed in volts (V), the rate of electron flow is measured in
amperes (A), and the resistance to electron flow is measured in ohms (Ω).
VOLT (V) - the electric potential difference required to produce one ampere of current in a
circuit having one ohm of resistance.
AMPERE (A) - the current that exists when a potential difference of one volt is applied to a
circuit having one ohm of resistance.
OHM (Ω) - the resistance required to limit the current to one ampere when a potential difference
of one volt is applied.
The diagram indicates the Ohm's law relationship between voltage (E), current (I), and
resistance (R). You should use this diagram as an aid in finding E, I, or R when the other two
terms are known.