For the circuit element of Problem 2.3, calculate (a) the instantaneous power absorbed, (b) the real power (state whether it is delivered or absorbed). (c) the reactive power (state whether delivered or absorbed). (d) the power factor (state whether lagging or leading).
[Note: By convention the power factor
Want to see the full answer?
Check out a sample textbook solutionChapter 2 Solutions
POWER SYS. ANALYSIS+DESIGN
- ") For the circuit shown, answer the questions from 7 to 10. The voltage and current given are in RMS values -/21 80 j6N 5020° V 40Z20° V 7) The apparent power consumed by the 4 ohms resistor is ...... VA: a) 4.38 2-152 e) 13.45 b) 24 0 22.48 c) 4.76 g) 4.38 d) 8.76 h) None of the above 8) The complex power supplied by the 50 volts source is..... VA: c) 200+j147 g) 145.67 Z 23.36° d) 145+j0 h) None of the above b) 84,67 2-154.36° a) 125-j87.5 e) 289.65 Z 85.23 0 244.52 30.12° 9) The power factor of the 50 volts source is.....: b) unity 10 707 lag b) 0.86 lag 00.707 lead c) 0.9 lag g) 0.8 lead d) 0.95 lag h) None of the above 1m The complex power consumed by the 8+j6 impedance is....VA: a) IN6 1236.87 e) 76 65 85.23 b) 423.6 2-21.36 0 142.05 Z 36.87 c) 239.1 Z 36.87° g) 523.7 Z 36.87° d) 423.6 36.87° h) None of the abovearrow_forward. Problem 2 The voltage and current at the terminals of a circuit element are shown. a) Is this circuit element a resistor, inductor, or capacitor? Explain your answer. b) What is the size of the circuit element? (Ohms, Henrys, or Farads) c) What is the instantaneous power being delivered to the circuit at t=1.5 s.? d) What is the RMS value of the current? T 2mA 2.MA "W SV ((SOC) V 1 (100)arrow_forwarda) Write down the expression of instantaneous voltage for an AC voltage having a Peak value of 220 Volts and a frequency of 50 Hz provided at time t=0, the instantaneous voltage is 220 Volts. What is the instantaneous voltage of the source at time “t = 5 seconds” What is its RMS voltage? b) Two 200Ω resistances are connected in series with one 0.5 H Inductance and two 100μF Capacitance with the power supply of part (a). (i)Draw the circuit diagram of the above network (ii)What is the total impedance of the circuit (iii)What is the max current that flows through the Inductance? (iv)What is the max current that flows through each of the Capacitance? (v)What is the power dissipated in the circuit (vi)What is the power factor of the circuit (vii)What is the resonance frequency of the circuit? (viii) What is the maximum power dissipated by the circuit when it is in resonancearrow_forward
- A single phase AC chopper supplies a pure inductive load of 0.02H from 220V, 50HZ AC supply. The triggering angle of the thyristors is 100°. (Assume the circuit is ideal.) a. Sketch the circuit b. Develop the load current expression and find the decay angle of the load current c. Sketch the load voltage and load current waveforms d. Calculate the RMS value of load voltage e. Calculate the RMS value of load current f. If the triggering angle of the thyristors is chosen as 60°. Explain the operation of the circuit.arrow_forwardAnswer by True or False • The addition of a series capacitor bank helps to improve the power factor and to compensate the reactive power, so the current drawn by the system load and capacitor is decreased and thus the losses and voltage drop are all reduced. • Harmonic currents increase the power factor, even when there is no phase angle between voltage and current • If the user consumes an active power P more than 75% of the reactive power Q, in addition to the electricity bill he must pay a penalty to the utility. • If a customer had a power factor in his installation less than 80%, he must pay a penalty to the utility • If 60% of current is converted into a useful work, the power factor is 0.4 • For sinusoidal (non-distorted, no Harmonics) currents, the displacement power factor is the same as the apparent power factor. Choose... Choose... Choose... Choose... Choose... Choose...arrow_forwardOne side of a transformer has 1,800 turns while the other side has 450 turns. The high voltage side is connected to a 240 Vrms source. The low voltage side (secondary) is connected to an impedance Z₁ = 20 +j10 0. For all questions requiring numerical answers, provide at least 2 digits after the decimal point. What is the voltage (in V rms) at the secondary? Answer: What is the current (in A rms) at the secondary? Answer: What is the current (in A rms) out of the source? Answer:arrow_forward
- The variable resistor Ro in the circuit shown is adjusted until maximum average power is delivered to Ro.1. a) What is the value of Ro in ohms?2. b) Calculate the average power delivered to Ro.3. c) If Ro is replaced with a variable impedance Zo, what is themaximum average power that can be delivered to Zo?4. d) In (c), what percentage of the circuit’s developed power isdelivered to the load Zo?arrow_forward2. a) An alternating current varying sinusoidally with a frequency of 50HZ has an RMS value of 20A. Write down the equation for the instantaneous value at 0.0025 second. In addition, find the time measured from a positive maximum value, will the instantaneous current be 14.14A? b) Assume that all lamps are identical. In this condition from your opinion which lamp(s) having more brightness, and which Lamb(s) will be low brightness as shown in figure2. A В E Figure 2 c) The resistance of the wire used for telephone is 35N per kilometer when the weight of the wire is 10kg per kilometer. If the specific resistance of the material is 1.95 x 10-82 – m. I. What is the cross-sectional area of the wire? I. What will be the resistance of a loop to a subscriber 8km from the exchange if wire of the same material but weighing 20kg per kilometer is used?arrow_forwardFill in the table for a correctly wired duplex outlet (U.S. National Electric Code standards for voltage PARAMETER EQUATION and frequency). Note the used of double- subscript notation. You can assume a 0° phase reference for Vba(t). Vba(t) Vea(t) Vbe(t) Vba (Peak Phasor) Vea (Peak Phasor) Vbc (Peak Phasor) Vba (RMS Phasor) Vea (RMS Phasor) Vbc (RMS Phasor) A Carrow_forward
- Short Problem: Given a parallel RLC circuit comprised of the following element: 55.27-ohm resistor, ideal inductor with reactance of 33.87 ohms; and a capacitor with reactance of 14.68 ohms. Compute for reactive power in VArs given an ac voltage source of 100 cis 0 volts. Give only the absolute value. Note: Follow this reminder carefully. Compute to the nearest 4 decimal places. No Scientific notation. Do not round off in the middle of calculation. Use stored values. Write the numerical values only. No units in your final answer. Spaces are not allowed. Excessive number of decimals as compared to the required number of decimals may result to an incorrect answer.arrow_forwardGiven a parallel RLC circuit comprised of the following element: 72.06-ohm resistor, ideal inductor with reactance of 69.81 ohms; and a capacitor with reactance of 10.98 ohms. Compute for reactive power in VArs given an ac voltage source of 100 cis 0 volts. Give only the absolute value. PLEASE ANSWER WITHIN 30 MINUTES. Round off to the nearest 4 decimal places. No Scientific notation. Do not round off in the middle of calculation. Use stored values. Write the numerical values only. No units in your final answer. Spaces are not allowed.arrow_forwardProblem #7) Specify whether each of the statements are TRUE or FALSE. D Reactive Power is a measure of the average power consumed by reactive (capacitive and inductive) loads. When connected to an AC voltage source, the instantaneous power (rate of energy transfer) supplied to a resistor varies at a frequency that is 2x the frequency of the applied source voltage. The magnitude of the impedance of a capacitor supplied by an AC source will increase as the source frequency increases. An AC source that has an RMS magnitude of 100V will supply the same average power to a resistor compared to a 100V DC source. The voltage across a capacitor is proportional to the rate of change of the current flowing through the capacitor. The magnitude of the impedance of a resistor supplied by an AC source does not vary as the source frequency increases. A complex impedance Z=R+jX, that has non-zero resistive and reactive components, will consume both real and reactive power when supplied by an AC source.…arrow_forward
- Introductory Circuit Analysis (13th Edition)Electrical EngineeringISBN:9780133923605Author:Robert L. BoylestadPublisher:PEARSONDelmar's Standard Textbook Of ElectricityElectrical EngineeringISBN:9781337900348Author:Stephen L. HermanPublisher:Cengage LearningProgrammable Logic ControllersElectrical EngineeringISBN:9780073373843Author:Frank D. PetruzellaPublisher:McGraw-Hill Education
- Fundamentals of Electric CircuitsElectrical EngineeringISBN:9780078028229Author:Charles K Alexander, Matthew SadikuPublisher:McGraw-Hill EducationElectric Circuits. (11th Edition)Electrical EngineeringISBN:9780134746968Author:James W. Nilsson, Susan RiedelPublisher:PEARSONEngineering ElectromagneticsElectrical EngineeringISBN:9780078028151Author:Hayt, William H. (william Hart), Jr, BUCK, John A.Publisher:Mcgraw-hill Education,