Consider the circuit shown in the figure ( Figure 1 ) . Suppose the four resisto
ID: 2132839 • Letter: C
Question
Consider the circuit shown in the figure(Figure 1) . Suppose the four resistors in this circuit have the values R1 = 13? , R2 = 6.3? , R3 = 6.1? , and R4 = 11? , and that the emf of the battery is E = 18V .
Part A
Part B
Consider the circuit shown in the figure(Figure 1) . Suppose the four resistors in this circuit have the values R1 = 13? , R2 = 6.3? , R3 = 6.1? , and R4 = 11? , and that the emf of the battery is E = 18V . Find the current through each resistor using the rules for series and parallel resistors. Express your answers using two significant figures separated by commas. Find the current through each resistor using Kirchhoff's rules. Express your answers using two significant figures separated by commas.Explanation / Answer
Part A
R2 and R4 are in series: Req=R2+R4=6.3+11=17.3 ohm
Req is in parallel with R3 Req2=Req//R3=(17.3*6.1)/(17.3+6.1)=105.53/23.4=4.51 ohm
Req2 in series with R1 Req3=Req2+R1=13+4.51=17.51 ohm
the current in Req3 is I=18/17.51=1.03 A which is the same as in R1 so IR1=1.03 A
the voltage across R1 is VR1=1.03*13=13.39 V
so the voltage across Req2 is 18-13.39=4.61V
so the current in R3 IR3=4.63/6.1=0.76 A
and current in R2 and R4 is IR2=IR4=4.63/Req=4.63/17.3=0.26 A
Part B
KVL:
-18+ R3I3 +R1 I1=0 ==>-18+6.1I3+13I1=0
-R3I3+(R2+R4)I2=0==>-6.1I3+17.3I2=0 ==> I2=6.1/17.3 I3=0.35 I3
and KCL I1=I2+I3
-18+6.1I3+13I1=0
-18+6.1I3+13(I2+I3)=0
-18+6.1I3+13(0.35 I3+I3)=0
-18+6.1I3+17.55I3=0==> I3=18/(6.1+17.55)= 0.76A
I2=0.35*0.76= 0.26A
and I1=I2+I3=0.76+0.26=1.03A