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barcode in vb.net 2010 Vector diagram in Software
176 Vector diagram Recognizing USS Code 39 In None Using Barcode Control SDK for Software Control to generate, create, read, scan barcode image in Software applications. Drawing Code 39 Extended In None Using Barcode generation for Software Control to generate, create Code39 image in Software applications. showing the phase angle for a purely capacitive impedance of 0 j40. The R and jX scales are relative. Reading ANSI/AIM Code 39 In None Using Barcode scanner for Software Control to read, scan read, scan image in Software applications. Painting Code39 In C#.NET Using Barcode generation for Visual Studio .NET Control to generate, create Code 39 Full ASCII image in Visual Studio .NET applications. True Power, VA Power, and Reactive Power 271
Code39 Drawer In .NET Framework Using Barcode generation for ASP.NET Control to generate, create ANSI/AIM Code 39 image in ASP.NET applications. Create Code 3 Of 9 In VS .NET Using Barcode maker for .NET Control to generate, create USS Code 39 image in VS .NET applications. 177 Vector diagram
Print Code 3/9 In VB.NET Using Barcode printer for .NET framework Control to generate, create Code 3/9 image in .NET applications. Code128 Printer In None Using Barcode creation for Software Control to generate, create Code128 image in Software applications. showing the phase angle for a complex impedance of 50 + j50. The R and jX scales are relative.
Code 39 Maker In None Using Barcode drawer for Software Control to generate, create Code 3 of 9 image in Software applications. Printing GS1  13 In None Using Barcode encoder for Software Control to generate, create EAN13 Supplement 5 image in Software applications. Problem 174 Suppose a circuit has an absolutevalue impedance Z of 100 , with a resistance R = 80 . What is the power factor Simply find the ratio PF = R/Z = 80/100 = 0.8 = 80%. Note that it doesn t matter whether the reactance in this circuit is capacitive or inductive. Problem 175 Suppose a circuit has an absolutevalue impedance of 50 , purely resistive. What is the power factor Here, R = Z = 50 . Therefore, PF = R/Z = 50/50 = 1 = 100%. Problem 176 Suppose a circuit has a resistance of 50 and a capacitive reactance of 30 in series. What is the power factor Use the cosine method. First, find the phase angle. Remember the formula: = arctan (X/R), where X is the reactance and R is the resistance. Therefore, = arctan ( 30/50) = arctan ( 0.60) = 31 . The power factor is the cosine of this angle; PF = cos ( 31 ) = 0.86 = 86%. Problem 177 Suppose a circuit has a resistance of 30 and an inductive reactance of 40 . What is the power factor Use the R/Z method. Find the absolutevalue impedance: Z 2 = R 2 + X 2 = 30 2 + 40 2 = 900 + 1600 = 2500. Therefore, Z = 25001/2 = 50 , so PF = R/Z = 30/50 = 0.60 = 60%. This problem can be represented vectorially by a 30:40:50 right triangle, as shown in Fig. 178. How Much of the Power Is True The preceding formulas allow you to figure out, given the resistance, reactance, and VA power, how many watts are true or real power, and how many watts are imaginary or reactive power. This is important in RF equipment, because some RF wattmeters display VA power rather than true power. When there is reactance in a circuit or system, the wattage reading is therefore exaggerated. EAN / UCC  14 Creation In None Using Barcode creation for Software Control to generate, create GS1128 image in Software applications. Paint UCC  12 In None Using Barcode drawer for Software Control to generate, create UPCA Supplement 5 image in Software applications. 272 Power and Resonance in AlternatingCurrent Circuits
MSI Plessey Drawer In None Using Barcode creator for Software Control to generate, create MSI Plessey image in Software applications. Generating GS1128 In None Using Barcode maker for Font Control to generate, create UCC  12 image in Font applications. 178 Illustration for
1D Maker In VS .NET Using Barcode drawer for ASP.NET Control to generate, create Linear image in ASP.NET applications. Drawing USS Code 128 In Java Using Barcode drawer for Java Control to generate, create Code128 image in Java applications. Problem 177. (The vertical and horizontal scale increments differ; this is a common practice in graphs, often done for illustration convenience.) Code 39 Full ASCII Encoder In Visual Studio .NET Using Barcode generation for .NET Control to generate, create Code 3 of 9 image in .NET framework applications. GS1  12 Drawer In ObjectiveC Using Barcode creator for iPad Control to generate, create UPC Symbol image in iPad applications. Problem 178 Suppose a circuit has 50 of resistance and 30 of inductive reactance in series. A wattmeter shows 100 W, representing the VA power. What is the true power First, calculate the power factor. Suppose you use the phaseangle method. Then: Data Matrix ECC200 Creator In Visual C#.NET Using Barcode creator for VS .NET Control to generate, create Data Matrix ECC200 image in VS .NET applications. Linear Generator In VB.NET Using Barcode encoder for .NET Control to generate, create 1D image in Visual Studio .NET applications. = arctan (X/R ) = arctan (30/50) = 31 The power factor is the cosine of the phase angle. Thus: PF = cos 31 = 0.86 = 86% Remember that PF = PT/PVA. This formula can be rearranged to solve for true power: PT = PF PVA = 0.86 100 = 86 W Problem 179 Suppose a circuit has a resistance of 1000 in parallel with a capacitance of 1000 pF. The frequency is 100 kHz. If a wattmeter designed to read VA power shows a reading of 88.0 W, what is the true power This problem is rather complicated because the components are in parallel. To begin, be sure the units are all in agreement so the formulas will work right. Convert the frequency to megahertz: f = 100 kHz = 0.100 MHz. Convert capacitance to microfarads: C = 1000 pF = 0.001000 F. From the previous chapter, recall the formula for capacitive susceptance, and calculate it for this situation: BC = 6.28f C = 6.28 0.100 0.001000 = 0.000628 S
Power Transmission 273
The conductance of the resistor, G, is the reciprocal of the resistance, R, as follows: G = 1/R = 1/1000 = 0.001000 S Now, use the formulas for calculating resistance and reactance in terms of conductance and susceptance in parallel circuits. First, find the resistance: R = G/(G 2 + B 2) = 0.001000/(0.0010002 + 0.0006282) = 0.001000/0.000001394 = 717 Then, find the reactance: X = B/(G 2 + B 2) = 0.000628/0.000001394 = 451 Next, calculate the phase angle: = arctan (X/R) = arctan ( 451/717) = arctan ( 0.629) = 32.2 The power factor is found from the phase angle as follows: PF = cos = cos ( 32.2 ) = 0.846 = 84.6% The VA power, PVA, is given as 88.0 W. Therefore: PT = PF PVA = 0.846 88.0 = 74.4 W

