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Problems Section 5.2 Source Transformations

P 5.2-1 The circuit shown in Figure P 5.2-1a has been divided into two parts. The circuit shown in

Figure P 5.2-1b was obtained by simplifying the part to the right of the terminals using source transformations. The part of the circuit to the left of the terminals was not changed.

(a) Determine the values of R t and v t in Figure P 5.2-1b. (b) Determine the values of the current i and the voltage v in Figure P 5.2-1b. The circuit in Figure P 5.2-1b is equivalent to the circuit in Figure P 5.2-1a. Consequently, the current i and the voltage v in Figure P 5.2-1a have the same values as do the current i and the voltage v in Figure P 5.2-1b. (c) Determine the value of the current ia in Figure P 5.2-1a.

FIGURE P 5.2-1

P 5.2-2 Consider the circuit of Figure P 5.2-2. Find ia by simplifying the circuit (using source transformations) to a single-loop circuit so that you need to write only one KVL equation to find ia.

FIGURE P 5.2-2

P 5.2-3 Find v o using source transformations if

in the circuit shown in Figure P 5.2-3.

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FIGURE P 5.2-3 Hint: Reduce the circuit to a single mesh that contains the voltage source labeled v o. Answer: v o = 28 V

P 5.2-4 Determine the value of the current ia in the circuit shown in Figure P 5.2-4.

FIGURE P 5.2-4

P 5.2-5 Use source transformations to find the current ia in the circuit shown in Figure P 5.2-5.

FIGURE P 5.2-5 Answer: ia = 1 A

P 5.2-6 Use source transformations to find the value of the voltage v a in Figure P 5.2-6.

FIGURE P 5.2-6 Answer: edugen.wileyplus.com/edugen/courses/crs5596/dorf1571/dorf1571c05/ZG9yZjE1NzFjMDVfMTNfMC54Zm9ybQ.enc?course=crs5596&id=ref

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va = 7 V

*P 5.2-7 Determine the power supplied by each of the sources in the circuit shown in Figure P 5.2-7.

FIGURE P 5.2-7

P 5.2-8 The circuit shown in Figure P 5.2-8 contains an unspecified resistance R. (a) Determine the value of the current i when R = 4 Ω. (b) Determine the value of the voltage v when R = 8 Ω. (c) Determine the value of R that will cause i = 1 A. (d) Determine the value of R that will cause v = 16 V.

FIGURE P 5.2-8

P 5.2-9 Determine the value of the power supplied by the current source in the circuit shown in Figure P 5.2-9.

FIGURE P 5.2-9 edugen.wileyplus.com/edugen/courses/crs5596/dorf1571/dorf1571c05/ZG9yZjE1NzFjMDVfMTNfMC54Zm9ybQ.enc?course=crs5596&id=ref

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Section 5.3 Superposition

P 5.3-1 The inputs to the circuit shown in Figure P 5.3-1 are the voltage source voltages v 1 and v 2. The output of the circuit is the voltage v o. The output is related to the inputs by

where a and b are constants. Determine the values of a and b.

FIGURE P 5.3-1

P 5.3-2 A particular linear circuit has two inputs, v 1 and v 2, and one output, v o. Three measurements are made. The first measurement shows that the output is v o = 4 V when the inputs are v 1= 2 V and v 2 = 0. The second measurement shows that the output is v o = 10 V when the inputs are v 1= 0 and v 2 = −2.5 V. In the third measurement, the inputs are v 1 = 3 V and v 2 = 3 V. What is the value of the output in the third measurement?

P 5.3-3 The circuit shown in Figure P 5.3-3 has two inputs, v s and is, and one output io. The output is related to the inputs by the equation

Given the following two facts:

and

Determine the values of the constants a and b and the values of the resistances are R 1 and R 2.

FIGURE P 5.3-3 Answer: a = 0.6 A/A, b = 0.02 A/V, R 1 = 30 Ω, and R 2 = 20 Ω.

P 5.3-4 Use superposition to find v for the circuit of Figure P 5.3-4.

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FIGURE P 5.3-4

P 5.3-5 Use superposition to find i for the circuit of Figure P 5.3-5.

FIGURE P 5.3-5 Answer: i = −2 mA

P 5.3-6 Use superposition to find i for the circuit of Figure P 5.3-6.

FIGURE P 5.3-6 Answer: i = 3.5 mA

P 5.3-7 Use superposition to find the value of the voltage v a in Figure P 5.3-7.

FIGURE P 5.3-7 Answer: va = 7 V

P 5.3-8 Use superposition to find the value of the current ix in Figure P 5.3-8.

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FIGURE P 5.3-8 Answer:

P 5.3-9 The input to the circuit shown in Figure P 5.3-9a is the voltage source voltage v s. The output is the voltage v o. The current source current, ia, is used to adjust the relationship between the input and output. The plot shown in Figure P 5.3-9b specifies a relationship between the input and output of the circuit. Design the circuit shown in Figure P 5.3-9a to satisfy the specification shown in Figure P 5.3-9b.

FIGURE P 5.3-9 Hint: Use superposition to express the output as v o = cv s + dia where c and d are constants that depend on R 1, R 2, and A. Specify values of R 1, R 2, and A to cause the required value of c. Finally, specify a value of ia to cause the required value of dia.

P 5.3-10 The input to the circuit shown in Figure P 5.3-10 is the voltage source voltage, v s. The output is the voltage v o. The current source current, ia, is used to adjust the relationship between the input and output. Design the circuit so that input and output are related by the equation v o = 2v s + 9.

FIGURE P 5.3-10 edugen.wileyplus.com/edugen/courses/crs5596/dorf1571/dorf1571c05/ZG9yZjE1NzFjMDVfMTNfMC54Zm9ybQ.enc?course=crs5596&id=ref

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Hint: Determine the required values of A and ia.

P 5.3-11 The circuit shown in Figure P 5.3-11 has three inputs: v 1, v 2, and i3. The output of the circuit is v o. The output is related to the inputs by

where a, b, and c are constants. Determine the values of a, b, and c.

FIGURE P 5.3-11

P 5.3-12 Determine the voltage v o(t) for the circuit shown in Figure P 5.3-12.

FIGURE P 5.3-12

P 5.3-13 Determine the value of the voltage v o in the circuit shown in Figure P 5.3-13.

FIGURE P 5.3-13

*P 5.3-14 The circuit shown in Figure P 5.3-14 has two inputs, v 1 and v 2, and one output, v o. The output is related to the input by the equation

where a and b are constants that depend on R 1, R 2, and R 3. edugen.wileyplus.com/edugen/courses/crs5596/dorf1571/dorf1571c05/ZG9yZjE1NzFjMDVfMTNfMC54Zm9ybQ.enc?course=crs5596&id=ref

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(a) Use superposition to show that when R 3 = R 1 || R 2 and R 2 = nR 1,

(b) Design this circuit so that a = 4b.

FIGURE P 5.3-14

P 5.3-15 The input to the circuit shown in Figure P 5.3-15 is the current i1. The output is the voltage v o. The current i2 is used to adjust the relationship between the input and output. Determine values of the current i2 and the resistance, R, that cause the output to be related to the input by the equation

FIGURE P 5.3-15

P 5.3-16 Determine values of the current, ia, and the resistance, R, for the circuit shown in Figure P 5.3-16.

FIGURE P 5.3-16

P 5.3-17 The circuit shown in Figure P 5.3-17 has three inputs: v 1, i2, and v 3. The output of the circuit is the edugen.wileyplus.com/edugen/courses/crs5596/dorf1571/dorf1571c05/ZG9yZjE1NzFjMDVfMTNfMC54Zm9ybQ.enc?course=crs5596&id=ref

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current io. The output of the circuit is related to the inputs by

where a, b, and c are constants. Determine the values of a, b, and c.

FIGURE P 5.3-17

P 5.3-18 Using the superposition principle, find the value of the current measured by the ammeter in Figure P 5.3-18a.

FIGURE P 5.3-18 (a) A circuit containing two independent sources. (b) The circuit after the

ideal ammeter has been replaced by the equivalent short circuit and a label has been added to indicate the current measured by the ammeter, im .

Hint: Figure P 5.3-18b shows the circuit after the ideal ammeter has been replaced by the equivalent short circuit and a label has been added to indicate the current measured by the ammeter, im. Answer:

P 5.3-19 Using the superposition principle, find the value of the voltage measured by the voltmeter in Figure edugen.wileyplus.com/edugen/courses/crs5596/dorf1571/dorf1571c05/ZG9yZjE1NzFjMDVfMTNfMC54Zm9ybQ.enc?course=crs5596&id=ref

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P 5.3-19a.

FIGURE P 5.3-19 (a) A circuit containing two independent sources. (b) The circuit after the

ideal voltmeter has been replaced by the equivalent open circuit and a label has been added to indicate the voltage measured by the voltmeter, vm .

Hint: Figure P 5.3-19b shows the circuit after the ideal voltmeter has been replaced by the equivalent open circuit and a label has been added to indicate the voltage measured by the voltmeter, v m. Answer:

Section 5.4 Thévenin's Theorem

P 5.4-1 Determine values of Rt and v oc that cause the circuit shown in Figure P 5.4-1b to be the Thévenin equivalent circuit of the circuit in Figure P 5.4-1a.

FIGURE P 5.4-1 Hint: Use source transformations and equivalent resistances to reduce the circuit in Figure P 5.4-1a until it is the circuit in Figure P 5.4-1b. Answer: R t = 5 Ω and v oc = 2 V

P 5.4-2 The circuit shown in Figure P 5.4-2b is the Thévenin equivalent circuit of the circuit shown in Figure P 5.4-2a. Find the value of the open-circuit voltage, v oc, and Thévenin resistance, Rt .

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FIGURE P 5.4-2 Answer: v oc = −12 V and R t = 16 Ω

P 5.4-3 The circuit shown in Figure P 5.4-3b is the Thévenin equivalent circuit of the circuit shown in Figure P 5.4-3a. Find the value of the open-circuit voltage, v oc, and Thévenin resistance, Rt .

FIGURE P 5.4-3 Answer: v oc = 2 V and R t = 4 Ω

P 5.4-4 Find the Thévenin equivalent circuit for the circuit shown in Figure P 5.4-4.

FIGURE P 5.4-4

P 5.4-5 Find the Thévenin equivalent circuit for the circuit shown in Figure P 5.4-5.

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FIGURE P 5.4-5 Answer: v oc = −2 V and R t = −8/3 Ω

P 5.4-6 Find the Thévenin equivalent circuit for the circuit shown in Figure P 5.4-6.

FIGURE P 5.4-6

P 5.4-7 The circuit shown in Figure P 5.4-7 has four unspecified circuit parameters: v s, R1, R2, and d, where d is the gain of the CCCS.

(a) Show that the open-circuit voltage, v oc, the short-circuit current, isc, and the Thévenin resistance, R t , of this circuit are given by

and

(b) Let R 1 = R 2 = 1 kΩ. Determine the values of v s and d required to cause v oc = 5 V and R t = 625 Ω.

FIGURE P 5.4-7

P 5.4-8 A resistor, R, was connected to a circuit box as shown in Figure P 5.4-8. The voltage, v, was measured. The resistance was changed, and the voltage was measured again. The results are shown in the table. Determine the Thévenin equivalent of the circuit within the box and predict the voltage, v, when R = 8 kΩ.

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FIGURE P 5.4-8

P 5.4-9 A resistor, R, was connected to a circuit box as shown in Figure P 5.4-9. The current, i, was measured. The resistance was changed, and the current was measured again. The results are shown in the table.

(a) Specify the value of R required to cause i = 2 mA. (b) Given that R > 0, determine the maximum possible value of the current i.

FIGURE P 5.4-9 Hint: Use the data in the table to represent the circuit by a Thévenin equivalent.

P 5.4-10 Measurements made on terminals a–b of a linear circuit, Figure P 5.4-10a, which is known to be made up only of independent and dependent voltage sources and current sources and resistors, yield the current–voltage characteristics shown in Figure P 5.4-10b. Find the Thévenin equivalent circuit.

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FIGURE P 5.4-10

P 5.4-11 For the circuit of Figure P 5.4-11, specify the resistance R that will cause current ib to be 2 mA. The current ia has units of amps.

FIGURE P 5.4-11 Hint: Find the Thévenin equivalent circuit of the circuit connected to R.

P 5.4-12 For the circuit of Figure P 5.4-12, specify the value of the resistance R L that will cause current iL to be −2 A.

FIGURE P 5.4-12 Answer: edugen.wileyplus.com/edugen/courses/crs5596/dorf1571/dorf1571c05/ZG9yZjE1NzFjMDVfMTNfMC54Zm9ybQ.enc?course=crs5596&id=ref

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R L = 12 Ω

P 5.4-13 The circuit shown in Figure P 5.4-13 contains an adjustable resistor. The resistance R can be set to any value in the range 0 ≤ R ≤ 100 kΩ.

(a) Determine the maximum value of the current ia that can be obtained by adjusting R. Determine the corresponding value of R. (b) Determine the maximum value of the voltage v a that can be obtained by adjusting R. Determine the corresponding value of R. (c) Determine the maximum value of the power supplied to the adjustable resistor that can be obtained by adjusting R. Determine the corresponding value of R.

FIGURE P 5.4-13

P 5.4-14 The circuit shown in Figure P 5.4-14 consists of two parts, the source (to the left of the terminals) and the load. The load consists of a single adjustable resistor having resistance 0 ≤ R L ≤ 20 Ω. The resistance R is fixed but unspecified. When R L = 4 Ω, the load current is measured to be io = 0.375 A. When R L = 8 Ω, the value of the load current is io = 0.300 A. (a) Determine the value of the load current when R L = 10 Ω. (b) Determine the value of R.

FIGURE P 5.4-14

P 5.4-15 The circuit shown in Figure P 5.4-15 contains an unspecified resistance, R. Determine the value of R in each of the following two ways. (a) Write and solve mesh equations. (b) Replace the part of the circuit connected to the resistor R by a Thévenin equivalent circuit. Analyze the resulting circuit.

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FIGURE P 5.4-15

P 5.4-16 Consider the circuit shown in Figure P 5.4-16. Replace the part of the circuit to the left of terminals a–b by its Thévenin equivalent circuit. Determine the value of the current io.

FIGURE P 5.4-16

P 5.4-17 An ideal voltmeter is modeled as an open circuit. A more realistic model of a voltmeter is a large resistance. Figure P 5.4-17a shows a circuit with a voltmeter that measures the voltage v m. In Figure P 5.4-17b, the voltmeter is replaced by the model of an ideal voltmeter, an open circuit. The voltmeter measures v mi, the ideal value of v m.

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FIGURE P 5.4-17 As R m → ∞, the voltmeter becomes an ideal voltmeter, and v m → v mi. When R m < ∞, the voltmeter is not ideal, and v m > v mi. The difference between v m and v mi is a measurement error caused by the fact that the voltmeter is not ideal.

(a) Determine the value of v mi. (b) Express the measurement error that occurs when R m = 1000 Ω as a percentage of v mi. (c) Determine the minimum value of R m required to ensure that the measurement error is smaller than 2 percent of v mi.

P 5.4-18 Determine the Thévenin equivalent circuit for the circuit shown in Figure P 5.4-18.

FIGURE P 5.4-18

P 5.4-19 Given that

in the circuit shown in Figure P 5.4-19, consider these two observations:

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Determine the following: (a) The maximum value of iR and the value of R that causes iR to be maximal (b) The maximum value of v R and the value of R that causes v R to be maximal (c) The maximum value of

and the value of R that causes pR to be maximal

FIGURE P 5.4-19

P 5.4-20 Consider the circuit shown in Figure P 5.4-20. Determine (a) The value of v R that occurs when R = 9 Ω. (b) The value of R that causes v R = 5.4 V. (c) The value of R that causes iR = 300 mA.

FIGURE P 5.4-20 Section 5.5 Norton's Equivalent Circuit

P 5.5-1 The part of the circuit shown in Figure P 5.5-1a to the left of the terminals can be reduced to its Norton equivalent circuit, using source transformations and equivalent resistance. The resulting Norton equivalent circuit, shown in Figure P 5.5-1b, will be characterized by the parameters:

(a) Determine the values of (b) Given that power, p = vi.

and R 1. , determine the maximum values of the voltage, v, and of the

Answer: edugen.wileyplus.com/edugen/courses/crs5596/dorf1571/dorf1571c05/ZG9yZjE1NzFjMDVfMTNfMC54Zm9ybQ.enc?course=crs5596&id=ref

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,

and

.

FIGURE P 5.5-1

P 5.5-2 Two black boxes are shown in Figure P 5.5-2. Box A contains the Thévenin equivalent of

some linear circuit, and box B contains the Norton equivalent of the same circuit. With access to just the outsides of the boxes and their terminals, how can you determine which is which, using only one shorting wire?

FIGURE P 5.5-2 Black boxes problem.

P 5.5-3 Find the Norton equivalent circuit for the circuit shown in Figure P 5.5-3.

FIGURE P 5.5-3 Answer: R t = 2 Ω and isc = −7.5 A

P 5.5-4 Find the Norton equivalent circuit for the circuit shown in Figure P 5.5-4.

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FIGURE P 5.5-4

P 5.5-5 The circuit shown in Figure P 5.5-5b is the Norton equivalent circuit of the circuit shown in

Figure P 5.5-5a. Find the value of the short-circuit current, isc, and Thévenin resistance, R t .

FIGURE P 5.5-5 Answer: isc = 1.13 A and R t = 7.57 Ω

P 5.5-6 The circuit shown in Figure P 5.5-6b is the Norton equivalent circuit of the circuit shown in

Figure P 5.5-6a. Find the value of the short-circuit current, isc, and Thévenin resistance, R t .

FIGURE P 5.5-6 Answer: isc = −24 A and R t = −3 Ω

P 5.5-7 Determine the value of the resistance R in the circuit shown in Figure P 5.5-7 by each of the following methods:

(a) Replace the part of the circuit to the left of terminals a–b by its the Norton equivalent circuit. Use current division to determine the value of R. (b) Analyze the circuit shown Figure P 5.5-7 using mesh equations. Solve the mesh equations to determine the value of R.

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FIGURE P 5.5-7

P 5.5-8 The device to the right of terminals a−b in Figure P 5.5-8 is a nonlinear resistor characterized by

Determine the values of i and v.

FIGURE P 5.5-8

P 5.5-9 Find the Norton equivalent circuit for the circuit shown in Figure P 5.5-9.

FIGURE P 5.5-9

P 5.5-10 Find the Norton equivalent circuit for the circuit shown in Figure P 5.5-10.

FIGURE P 5.5-10

P 5.5-11 edugen.wileyplus.com/edugen/courses/crs5596/dorf1571/dorf1571c05/ZG9yZjE1NzFjMDVfMTNfMC54Zm9ybQ.enc?course=crs5596&id=ref

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An ideal ammeter is modeled as a short circuit. A more realistic model of an ammeter is a small resistance. Figure P 5.5-11a shows a circuit with an ammeter that measures the current im. In Figure P 5.5-10b, the ammeter is replaced by the model of an ideal ammeter, a short circuit. The ammeter measures imi, the ideal value of im.

FIGURE P 5.5-11 As R m → 0, the ammeter becomes an ideal ammeter and im → imi. When R m > 0, the ammeter is not ideal and im < imi. The difference between im and imi is a measurement error caused by the fact that the ammeter is not ideal.

(a) Determine the value of imi. (b) Express the measurement error that occurs when R m = 20 Ω as a percentage of imi. (c) Determine the maximum value of R m required to ensure that the measurement error is smaller than 2 percent of imi.

P 5.5-12 Determine values of R t and isc that cause the circuit shown in Figure P 5.5-12b to be the Norton equivalent circuit of the circuit in Figure P 5.5-12a.

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FIGURE P 5.5-12 Answer: R t = 3 Ω and isc = −2 A

P 5.5-13 Use Norton's theorem to formulate a general expression for the current i in terms of the variable resistance R shown in Figure P 5.5-13.

FIGURE P 5.5-13 Answer: i = 20/(8 + R) A Section 5.6 Maximum Power Transfer

P 5.6-1 The circuit shown in Figure P 5.6-1 consists of two parts separated by a pair of terminals.

Consider the part of the circuit to the left of the terminals. The open circuit voltage is , and short-circuit current is . Determine the values of (a) the voltage source voltage, V s, and the resistance R 2 and (b) the resistance R that maximizes the power delivered to the resistor to the right of the terminals, and the corresponding maximum power.

FIGURE P 5.6-1

P 5.6-2 The circuit model for a photovoltaic cell is given in Figure P 5.6-2 (Edelson, 1992). The current is is proportional to the solar insolation (kW/m2).

(a) Find the load resistance, R L, for maximum power transfer. (b) Find the maximum power transferred when is = 1 A.

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FIGURE P 5.6-2 Circuit model of photovoltaic cell.

P 5.6-3 For the circuit in Figure P 5.6-3, (a) find R such that maximum power is dissipated in R and (b) calculate the value of maximum power.

FIGURE P 5.6-3 Answer: R = 60 Ω and P max = 54 mW

P 5.6-4 For the circuit in Figure P 5.6-4, prove that for Rs variable and RL fixed, the power dissipated in R L is maximum when R s = 0.

FIGURE P 5.6-4

P 5.6-5 Find the maximum power to the load RL if the maximum power transfer condition is met for the circuit of Figure P 5.6-5.

FIGURE P 5.6-5 Answer: max pL = 0.75 W

P 5.6-6 Determine the maximum power that can be absorbed by a resistor, R, connected to terminals a–b of the circuit shown in Figure P 5.6-6. Specify the required value of R.

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FIGURE P 5.6-6 Bridge circuit.

P 5.6-7 Figure P 5.6-7 shows a source connected to a load through an amplifier. The load can safely receive up to 15 W of power. Consider three cases:

(a) A = 20 V/V and R o = 10 Ω. Determine the value of R L that maximizes the power delivered to the load and the corresponding maximum load power. (b) A = 20 V/V and R L = 8 Ω. Determine the value of R o that maximizes the power delivered to the load and the corresponding maximum load power. (c) R o = 10 Ω and R L = 8 Ω. Determine the value of A that maximizes the power delivered to the load and the corresponding maximum load power.

FIGURE P 5.6-7

P 5.6-8 The circuit in Figure P 5.6-8 contains a variable resistance, R, implemented using a

potentiometer. The resistance of the variable resistor varies over the range 0 ≤ R ≤ 1000 Ω. The variable resistor can safely receive 1/4 W power. Determine the maximum power received by the variable resistor. Is the circuit safe?

FIGURE P 5.6-8

P 5.6-9 For the circuit of Figure P 5.6-9, find the power delivered to the load when RL is fixed and Rt may be varied between 1 Ω and 5 Ω. Select R t so that maximum power is delivered to R L.

FIGURE P 5.6-9 edugen.wileyplus.com/edugen/courses/crs5596/dorf1571/dorf1571c05/ZG9yZjE1NzFjMDVfMTNfMC54Zm9ybQ.enc?course=crs5596&id=ref

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Problems

Answer: 13.9 W

P 5.6-10 A resistive circuit was connected to a variable resistor, and the power delivered to the resistor was measured as shown in Figure P 5.6-10. Determine the Thévenin equivalent circuit.

FIGURE P 5.6-10 Answer: R t = 20 Ω and v oc = 20 V Section 5.8 Using PSpice to Determine the Thévenin Equivalent Circuit

P 5.8-1 The circuit shown in Figure P 5.8-1 is separated into two parts by a pair of terminals. Call the

part of the circuit to the left of the terminals circuit A and the part of the circuit to the right of the terminal circuit B. Use PSpice to do the following: (a) Determine the node voltages for the entire circuit. (b) Determine the Thévenin equivalent circuit of circuit A. (c) Replace circuit A by its Thévenin equivalent and determine the node voltages of the modified circuit. (d) Compare the node voltages of circuit B before and after replacing circuit A by its Thévenin equivalent.

FIGURE P 5.8-1 Section 5.9 How Can We Check …?

P 5.9-1 For the circuit of Figure P 5.9-1, the current i has been measured for three different values of R and is listed in the table. Are the data consistent?

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Problems

FIGURE P 5.9-1

P 5.9-2 Your lab partner built the circuit shown in Figure P 5.9-2 and measured the current i and

voltage v corresponding to several values of the resistance R. The results are shown in the table in Figure P 5.9-2. Your lab partner says that R L = 8000 Ω is required to cause i = 1 mA. Do you agree? Justify your answer.

FIGURE P 5.9-2

P 5.9-3 In preparation for lab, your lab partner determined the Thévenin equivalent of the circuit connected to R L in Figure P 5.9-3. She says that the Thévenin resistance is the open-circuit voltage is

and

. In lab, you built the circuit using R = 110 Ω and R L

= 40 Ω and measured that i = 54.5 mA. Is this measurement consistent with the prelab calculations? Justify your answers.

FIGURE P 5.9-3

P 5.9-4 Your lab partner claims that the current i in Figure P 5.9-4 will be no greater than 12.0 mA, regardless of the value of the resistance R. Do you agree?

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FIGURE P 5.9-4

P 5.9-5 Figure P 5.9-5 shows a circuit and some corresponding data. Two resistances, R1 and R, and the current source current are unspecified. The tabulated data provide values of the current, i, and voltage, v, corresponding to several values of the resistance R. (a) Consider replacing the part of the circuit connected to the resistor R by a Thévenin equivalent circuit. Use the data in rows 2 and 3 of the table to find the values of R t and v oc, the Thévenin resistance, and the open-circuit voltage. (b) Use the results of part (a) to verify that the tabulated data are consistent. (c) Fill in the blanks in the table. (d) Determine the values of R 1 and is.

FIGURE P 5.9-5

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