Question

In the circuit shown, the greatest voltage drop will occur across which of the following resistors?

R1, R2, R3, or R4 ?

Answer 1

at the first step the equivalent circuit is:

where R_0 is such that:
\[\Large {R_0} = \frac{1}{{\frac{1}{{13}} + \frac{1}{{18}}}} = ...\]

Answer 2

ok! so we get 7.548 ?

Answer 3

ok! R_0=7.55 ohms

Answer 4

yay:)

Answer 5

now the current is:
\[\large I = \frac{V}{{{R_{TOTAL}}}} = \frac{{15}}{{8.5 + 3.2 + 7.55}} = ...\]

Answer 6

so we get 0.779?

Answer 7

yes! we can round off that result to I=0.78 amperes

Answer 8

ok! what does that mean then?

Answer 9

now we have the subsequent voltage drop:
\[\large \begin{gathered}
{V_1} = {R_1}I = 8.5 \times 0.78 = ... \hfill \\
{V_{AB}} = {R_{AB}}I = 7.55 \times 0.78 = ... \hfill \\
{V_4} = {R_4}I = 3.2 \times 0.78 = ... \hfill \\
\end{gathered} \]

Answer 10

drops*