- Information
- AI Chat
Basic EEE
Bachelor of Science in Civil Engineering
Mindanao State University
Recommended for you
Preview text
Achievement Review
Unit 3, 4, 5 and 6
Electricity 2 by Thomas Kubala
Submitted by:
Crestine Lily O. Dongosa
BSCEN-CE
Submitted to:
Engr. Nelson Patriarca Benares
Basic EE Professor
Unit 3: Capacitance and Capacitive Reactance
ACHIEVEMENT REVIEW
In problems 1 through 10, select the best answer to make the statement true. Place the letter of the selected answer in the space provided.
The most generally used unit of capacitive reactance is the __________ a. farad. b. microfarad. c. ohm. d. henry. e. hertz.
Before a capacitor is handled, be sure it __________ a. is large enough to do the job. b. has clean plates. c. has proper polarity. d. is charged. e. is discharged.
The capacitor’s opposition to alternating current is called __________ a. capacitance. b. capacitive reactance. c. resistance. d. the farad. e. the microfarad.
Capacitive reactance of a circuit may be increased by __________ a. decreasing total capacitance. b. increasing total capacitance. c. increasing the number of farads. d. increasing source voltage. e. increasing frequency.
In a capacitive AC circuit __________
a. 0. b. 8. c. 43. d. 166. e. 332.
The total current, in amperes, of an AC circuit that has a total capacitance of 638 μF connected to a 120-V, 25-Hz source is __________. a. 4. b. 5. c. 8. d. 12. e. 25.
Find the current in the circuit shown in Figure 3-9. Figure 3-9 Finding current. Answer: I = 2
Change C to 40 μF in problem 11, and calculate the current. Answer: I = 3 A
Determine the total capacitive reactance in the circuit shown in Figure 3-10 and the value of C2 in microfarads if the total current equals 3 amperes. Figure 3-10 Total reactance. Answer: XCT = 50 Ω C2 = 20 μF
Using the circuit for problem 13 (Figure 3-10), change C1 to 50 μF, and the total current to 5 amperes. Find the total Xc and the value of C2. Answer: XCT = 29 Ω 30 Ω
C2 = 38 μF ≈ 40 μF
Find the total current in the circuit shown in Figure 3-11. Figure 3-11 Finding current. Answer: IT = 0 A
For the circuit in problem 15 (Figure 3-11), change the frequency to 60 Hz, and find the total current. Answer: IT = 1 A
Find XCt for the circuit shown in Figure 3-12. Figure 3-12 Finding reactance. Answer: XCT = 552 Ω
Using the circuit shown in problem 17 (Figure 3-12), change the 8-μF capacitor to 10 μF, and find the total capacitive reactance. Answer: XCT = 486 Ω
Unit 4 Series Circuit: Resistance and Inductance
ACHIEVEMENT REVIEW
c. 45°
The total impedance, in ohms, of the circuit shown in Figure 4-8 is __________. a. 15. Figure 4-8 Finding impedance. b. 20. c. 25. d. 29. e. 35.
A 40-ohm resistor is connected in series with a 0-hertz coil. The combination is connected to a 150-volt, 40-hertz source. The magnitude of total current, in amperes, is ____________. a. 2. d. 5. b. 3. e. 30. c. 3.
In the circuit shown in Figure 4-9, if ER = 21 volts and EL = 28 volts, perform the following: a. Find the value of ET. Answer: ET = 35 V
b. Find the value of R Answer: R = 5 Ω
c. Find the value of XL. Answer: XL = 7 Ω
d. Draw the voltage vector diagram showing ER, EL, and ET. Draw to scale. Answer:
ET = 35 V EL= 28V
Determine the voltage across the inductor shown in Figure 4-10. Answer: EL = 133 V
Using the circuit in problem 9 (Figure 4-10), change R to 20 ohms and find the voltage across it. Answer: EL = 142 V
Change the inductance in problem 9 to 0 H and find the voltage across the 25- ohm resistor. Answer: ER = 23 V
The impedance for the circuit in Figure 4-11 is 40 ohms. Find the total voltage, E, if the voltage across R is 100 volts. Answer: E = 160 V
Unit 5 Series Circuit: Resistance and Capacitance
ACHIEVEMENT REVIEW
Select the best answer for problems 1 through 7, and place the letter of the selected answer in the space provided.
- The current of an RC series AC circuit can be found with the expression __________
ɵ = 53° ER = 21 V
a. 1 A. Figure 5-8. Finding current. b. 2 A. c. 3 A. d. 4 A. e. 12 A.
In the circuit shown in Figure 5-9, if the voltage across R2 is 60 volts, the value of voltage across the capacitor is __________. a. 40 V. Figure 5-9. Finding capacitor voltage. b. 60 V. c. 90 V. d. 130 V. e. E.
A 40-Ω resistor is connected in series with an 88-μF capacitor. The combination is across a 220-V, 60-Hz source. Find the magnitude of circuit current. Answer: I = 4 A
In the circuit shown in Figure 5-10, what is the voltage across R? Figure 5-10 Finding resistor voltage. Answer: ER = 312 V
10. For the circuit in problem 9 (Figure 5-10), find the voltage across C.
Answer: EC = 249 V 250 V
11. Draw the voltage vector diagram for the circuit in problem 9 (Figure 5-
10).
Answer:
ER = 312 V
ɵ = 38°
ET = 399 V 400V EC = 249 V 250 V
12. The voltage across the capacitor shown in Figure 5-11 is 120 volts. Find
the total circuit impedance.
Figure 5-11 Finding circuit impedance.
Answer: Z = 50 Ω
- For the circuit in problem 12 (Figure 5-11), if R1 equals 10 ohms, find R2. Answer: R2 = 10 Ω
Unit 6 Series Circuit: Resistance, Inductance, and Capacitance
ACHIEVEMENT REVIEW
In problems 1 through 7, select the best answer to complete the statement. Place the letter of the selected answer in the space provided.
If XC is greater than XL in a series RLC circuit, the __________
In the circuit shown in Figure 6-11, the current, in amperes, is __________. a. 0. b. 1. c. 2. d. 3. e. 5.
In the circuit shown in Figure 6-12, find the value of voltage across XC. Figure 6-12. Finding capacitive voltage. Answer: EXC = 300 V
For the circuit in problem 8 (Figure 6-12), change R to 40 ohms and calculate the circuit current. Answer: I = 2 A
Draw the voltage vector diagram for the circuit in problem 8 (Figure 6-12). Answer:
Find the source voltage, E, in the circuit shown in Figure 6-13. Figure 6-13. Finding source voltage. Answer: E = 300 V
XL = 60 Ω
R = 30Ω
ɵ = 53° Z = 50Ω X = XC – XL = 100Ω - 60 Ω = 40
XC = 100 Ω
The circuit shown in Figure 6-14 is at resonance. Determine the current and the inductive reactance. Figure 6-14. Circuit at resonance. Answer: I = 5 A XL = 30 Ω
Find the voltage across XC and the voltage across XL in the circuit for problem 12 (Figure 6-14). Answer: EXC = 150 V EXL = 150 V
Basic EEE
Course: Bachelor of Science in Civil Engineering
University: Mindanao State University
- Discover more from:
