A $2.0 - \Omega$ resistor is in series with a parallel combination of $4.0 - \Omega , 6.0 - \Omega$, and $12 - \Omega$ resistors. What is the equivalent resistance of this system?
A) $4.0 \Omega$
B) $1.8 \Omega$
C) $24 \Omega$
D) $2.7 \Omega$

Question

Quizplus · Accepted Answer

The equivalent resistance of the parallel combination is found using the formula $1/R_{eq} = 1/R_1 + 1/R_2 + 1/R_3$. For the $4.0 - \Omega , 6.0 - \Omega$, and $12 - \Omega$ resistors, this gives $1/R_{eq} = 1/4 + 1/6 + 1/12 = 1/2$, so $R_{eq} = 2.0 \Omega$. Adding this to the $2.0 - \Omega$ resistor in series gives a total equivalent resistance of $4.0 \Omega$.

A 2.0−Ω2.0 - \Omega2.0−Ω Resistor Is in Series with a Parallel Combination Of

A $2.0 - \Omega$ Resistor Is in Series with a Parallel Combination Of