## anonymous one year ago In the circuit shown, the greatest voltage drop will occur across which of the following resistors? R1, R2, R3, or R4 ?

1. anonymous

2. Michele_Laino

at the first step the equivalent circuit is: |dw:1434309387712:dw| where R_0 is such that: $\Large {R_0} = \frac{1}{{\frac{1}{{13}} + \frac{1}{{18}}}} = ...$

3. anonymous

ok! so we get 7.548 ?

4. Michele_Laino

ok! R_0=7.55 ohms

5. anonymous

yay:)

6. Michele_Laino

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

7. anonymous

so we get 0.779?

8. Michele_Laino

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

9. anonymous

ok! what does that mean then?

10. Michele_Laino

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

11. Michele_Laino

drops*

12. Michele_Laino

|dw:1434309867660:dw|

13. anonymous

ok so we get 6.63; 5.889; 2.496?

14. Michele_Laino

that's right!

15. Michele_Laino

now please keep in mind that the voltage drops across R_2 and R_3 are the same, and both of them is equal to 5.889 volts

16. Michele_Laino

oops...both of them are equal to...

17. anonymous

meaning that R4 would be the solution? since it is 3.2?

18. Michele_Laino

the greatest value is 6.63 volts

19. anonymous

ok what does that mean? :/

20. Michele_Laino

that means the greatest voltage drop is across the resistor R_1

21. anonymous

ohh okay:O sorry i got confused a bit! thank you:)

22. Michele_Laino

:)