Measuring Resistance
Resistance is the opposition to passage of an electric current. One Ohm (Ω) is the resistance through which one volt (V) of electric force causes one ampere (A) to flow. Two common methods for measuring resistance are the 2-wire method and the 4-wire method. Both methods send a current through a resistor with a measurement device measuring the voltage drop from the signal before and after it crosses the resistor. The 2-wire method is easier to implement, but this method is less accurate than the 4-wire method for resistances below 100 Ω. To calculate resistance, use the following equation.
R(Ω) = V(V) / I(A)
where R is the resistance, V is the voltage, and I is the current.