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Circuit variable problem

One method of checking calculations in volving interconnected circuit elements is to see that the total power delivered equals the total power absorbed... Please see attached.

Transient Power Analysis in Electric Circuits

The voltage and current at the terminals of the circuit elements in Fig 1.5 are zero for t<0 nad t<40s. In the interval between 4 and 40s the expressions are: (a) At what instant of time is the power being delivered to the circuit element maximum? (b) What is the power at the time found in part (a) (c) At what instant of t

Circuits problem

In electronic circuits it is not unusual to encounter currents in the microamperage range. Assume a 20 micro amp current, due to the flow of electrons. a) What is the average number of electrons per second that flow past a fixed reference cross section that is perpendicular to the direction of flow. b) Compare the size o

Circuit variable problem

A current of 1400 A exits in a rectangular (0.6 X 9.0)cm copper bus bar. The current is due to free electrons moving through the bus bar at an average velocity of v meters/second. If the concentration of free electrons is 10^29 electrons per cubic meter and if they are uniformly dispersed throughout the bus bar, then what is th

Transformer Load Impedance

In the following circuit find Ix and Iy by replacing the transformer and load at points x, x with the transformer load impedance.

Logic Circuit with 3D Flip Flops

Consider the attached circuit. Assume that the three states are initially at the 0 logic level. Which of the given tables is true for the function performed by this circuit? The leftmost column represents the clock pulses. Initially there is no pulse (1st row). As the first clock pulse arrives the resulting change of state is sh

Circuit analysis and resistance

Consider the following circuit. As shown, lossy current source drives 1Kohm load by means of a voltage divider circuit. It is desired to have 5mA flow through the load. R1 and R2 can be assigned any value. Part One: What is the smallest value that R2 can have? Part Two: What is the largest value that R1 can have?

Circuit Analysis with Sinusoidal Source Voltage

Consider the attached circuit. The sinusoidal source voltage is Vs(t)=20sin(2 pi t). The diode is ideal. What would the correct sketch of the source voltage and load voltage look like as a function of time?


A 4:1 step-down transformer uses a 60Vac source on the primary windings. There is 120mA flowing through the load resistance on the secondary windings. How do I find the resistive load?


How would I find the equivalent resistance R_ab of the following circuit?

Watts, Voltage

A 120 V house circuit (parallel) has the following bulbs and appliances turned on: 25 W, 40 W, 60 W, 900 W and 75 W. Find the equivalent resistance of these bulbs and appliances.

Efficiency and power of circuit

The equivalent circuit of Figure P3.57 has Vt = 35 V and Rt = 600 ohms. If the conditions for maximum power transfer exist, determine the value of RL, power of RL, and efficiency of the circuit. See diagram in attached file.

Mesh analysis of circuit

Using mesh analysis, find the voltage gain Av = V2/V1 in the circuit. See attached file for full problem description.

Three Zones of a Single Phase Circuit

Three zones of a single-phase circuit are identified in the figure attached. The zones are connected by two transformers T1 and T2, whose ratings are also shown in the same figure. Using base values of 20kVA and 115 volts in zone-3 calculate the per-unit impedances. Neglect the transformer winding resistances and the shunt admit

Communications Systems

A speech scrambler transforms low frequency to high frequency components and vice versa so that a baseband signal of bandwidth B is transformed to another baseband signal of the same bandwidth and a components at the frequency f is transformed into a component at the frequency B-f, where B is the bandwidth of the signal. An exam

Resonant Frequency of a Circuit

Refer to the diagram attached. 1. Calculate the resonant frequency of the circuit 2. Calculate the magnitude of the circuit current at resonance. 3. Calculate the value of VOUT at resonance. 4. Explain why the circuit current is capacitive (i.e. leads the supply voltage) at very low frequencies and inductive at very high fr

Fault Tolerant Volume Control

In a certain application the following circuit serves as a fault tolerant volume control. What value must the potentiometer (P) be in order for the total resistance to be 50ohms?

Virtual Circuits

The following design problem concerning implementation of virtual circuit service. If virtual circuits are used internal to the subnet, each data packet must have a 3-byte header, and each router must tie up 8 bytes of storage for circuit identification. If datagrams are used internally, 15-byte headers are needed, but no router

Question about Electrical Energy Conversion

A 100 kVA, 60 Hz, 7200/480 V, single-phase transformer has the following parameters (all expressed in ohms): RHV = 3.06 RLV = 0.014 XHV = 6.05 XLV = 0.027 Xm,HV = 17,809 Re,HV = 71,400 The transformer supplies a load that draws rated current at 0.75 power factor lagging at 480 V at the load. Sketch the approximate eq

Two power sources in a circuit

I need to find the voltmeter reading and how to deal with 2 power sources Is this going into Thevenins or Kirchoff's? (Please see the attachment.)

Please, show me how you got the answers and give me the answers. Thanks

1. A series RL circuit containing a 0.17-H inductor has a time constant of 0.13 s. What is the resistance in the circuit? 2. A 1000-ohm's resistor is joined in series with a 400-mH inductance and a 12-V battery. (a) What is the time constant of the circuit? (b) How long will it take after the circuit is completed for voltage

Charge flow from one capacitor to another

Why and how does charge flow from one capacitor to another capacitor when the two are connected to each other by a conducting wire? I am not able to understand that; why and how does negative charge flow from a capacitor having lower potential difference between its plates to a capacitor having higher potential difference betwe

RC Circtuit with Expulsion = 12.0 votes

Consider an RC circuit with epsilon = 12.0 V, R = 175 ohms, and C = 55.7 micro-F. Find (a) the time constant for the circuit, (b) the maximum charge on the capacitor, and (c) the initial current in the circuit.

LRC Circuits

Please refer to the attached file. How much should damping ( ) affect the result of the angular frequency for impulse response? (see attachment) In equation XVI.5, the details of the differentiation of I(t) are omitted. Take the derivative of I(t) and explicitly show how the voltage across the inductor L varies with time.