Ect 122

1. Each of the following resistor combinations is connected as shown in Figure 4.29. For each combination, calculate the total circuit resistance.

a) 2650 Ω, or 2.65 kΩ.

b) 275 Ω.

c) 1241 Ω, or 1.241 kΩ.

d) 106400 Ω, or 106.4 kΩ.

3. The following resistor combinations are for a circuit like the one shown in Figure 4.30. In each case, determine the unknown resistor value.

a) R3 = 1.9 kΩ - 1.43 kΩ = 470 Ω.

b) R1 = 165 kΩ - 138 kΩ = 27 kΩ.

c) R2 = 44.3 kΩ - 39.2 kΩ = 5.1 kΩ.

d) RT = 27 Ω + 39 Ω + 82 Ω = 148 Ω.

8. Calculate the total current for the circuit shown in Figure 4.32b.

b) RT= R1+ R2=1000+10000=11000 Ω . IT=VRT=511000=4.54 A.

16. Calculate the value of the source voltage in Figure 4.34b.

b) RT= R1+ R2=22000+10000=32000 Ω . V=I* RT=0.0005*32000=16 V.

23. Write the Kirchhoff’s loop equation for the circuit shown in Figure 4.36a, and verify that the voltages add up to 0 V.

Kirchhoff’s Voltage Law: VS=V1+V2+…+Vn , and VS+V1+V2+…+Vn=0 V.

a) 7 + 2 + 6 = 15 – 15 (VS) = 0 V.

26. Calculate the value of the current in Figure 4.37b

b) VR1=VS-VR2=12-3=9 V… VR1VS=R1RT , so9 V12 V=150 ΩRT≫RT=200 Ω .

R2=RT-R1=200-150=50 Ω … I=VRT=12200=0.06 A.

30. For the circuit shown in Figure 4.38b, calculate the voltage from point A to ground.

b) (VR2+VR3)= VS(R2+R3)RT=9195000222000=7.905 V.

40. Calculate the component voltage and power values for the circuit shown in Figure 4.41b, along with the circuit values of RT, IT and PT

b) V1=VSR1RT=16 1200075500=2.543 V.. V2=VSR2RT=16 6200075500=13.139 V.. V3=VS-V1+V2=16-15.682=0.318 V >> VR1=2.543 V;VR2=13.139 V;VR3=0.318 V;RT=75.5 kΩ .

IT=VRT=1675500=2.119 A.. PT=V*IT=16*2.119=33.904 W.

46. A 15 V source is connected to a 910 Ω resistor with a 5% tolerance. Calculate the maximum value of circuit current. [Chapter 2]

Rmax= 910+45.5= 955.5 Ω >> Imax=VRmax=15955.5= 0.0156 A, or 15.6 mA.

47. Convert the following values to engineering notation...