For the circuit in Fig. 4.111, obtain the Thevenin

Calculate the current in the circuit of Fig. 4.69. What value of input voltage is necessary to make equal to 5 amps?

Using Fig. 4.70, design a problem to help other students better understand linearity.

(a) In the circuit of Fig. 4.71, calculate and when (b) Find and when (c) What are and when each of the resistors is replaced by a resistor and vs 10 V? 10- vo io 1- i vs 10 V. vo o vs 1 V. i vo o + 1

Use linearity to determine in the circuit of Fig. 4.72.

For the circuit in Fig. 4.73, assume and use linearity to find the actual value of .

For the linear circuit shown in Fig. 4.74, use linearity to complete the following table.

Use linearity and the assumption that to find the actual value of in Fig. 4.75.

Using superposition, find in the circuit of Fig. 4.76. Check with PSpice or MultiSim.

Given that I 4 amps when Vs 40 volts and Is 4 amps and I 1 amp when Vs 20 volts and Is 0, use superposition and linearity to determine the value of I when Vs 60 volts and Is 2 amps. Proble

Using Fig. 4.78, design a problem to help other students better understand superposition. Note, the letter k is a gain you can specify to make the problem easier to solve but must not be zero.

Use the superposition principle to find and in the circuit of Fig. 4.79.

Determine in the circuit of Fig. 4.80 using the superposition principle.

Use superposition to find in the circuit of Fig. 4.81.

Apply the superposition principle to find in the circuit of Fig. 4.82.

For the circuit in Fig. 4.83, use superposition to find i. Calculate the power delivered to the resistor.

Given the circuit in Fig. 4.84, use superposition to obtain i0.

Use superposition to obtain in the circuit of Fig. 4.85. Check your result using PSpice or MultiSim.

Use superposition to find in the circuit of Fig. 4.86.

Use superposition to solve for in the circuit of Fig. 4.87.

Use source transformation to reduce the circuit in Fig. 4.88 to a single voltage source in series with a single resistor

Using Fig. 4.89, design a problem to help other students better understand source transformation.

For the circuit in Fig. 4.90, use source transformation to find i.

Referring to Fig. 4.91, use source transformation to determine the current and power absorbed by the 8- resistor.

Use source transformation to find the voltage in the circuit of Fig. 4.92.

Obtain in the circuit of Fig. 4.93 using source transformation. Check your result using PSpice or MultiSim.

Use source transformation to find in the circuit of Fig. 4.94.

Apply source transformation to find in the circuit of Fig. 4.95.

Use source transformation to find in Fig. 4.96.

Use source transformation to find in the circuit of Fig. 4.97.

Use source transformation on the circuit shown in Fig 4.98 to find ix.

Determine in the circuit of Fig. 4.99 using source transformation.

Use source transformation to find in the circuit of Fig. 4.100.

Determine the Thevenin equivalent circuit, shown in Fig. 4.101, as seen by the 5-ohm resistor. Then calculate the current flowing through the 5-ohm resistor.

Using Fig. 4.102, design a problem that will help other students better understand Thevenin equivalent circuits.

Use Thevenins theorem to find in Prob. 4.12.

Solve for the current i in the circuit of Fig. 4.103 using Thevenins theorem. (Hint: Find the Thevenin equivalent seen by the 12- resistor.)

Find the Norton equivalent with respect to terminals a-b in the circuit shown in Fig. 4.104.

Apply Thevenins theorem to find in the circuit of Fig. 4.105.

Obtain the Thevenin equivalent at terminals of the circuit shown in Fig. 4.106.

Find the Thevenin equivalent at terminals of the circuit in Fig. 4.107.

Find the Thevenin and Norton equivalents at terminals of the circuit shown in Fig. 4.108.

For the circuit in Fig. 4.109, find the Thevenin equivalent between terminals a and b.

Find the Thevenin equivalent looking into terminals of the circuit in Fig. 4.110 and solve for ix a-b .

For the circuit in Fig. 4.111, obtain the Thevenin equivalent as seen from terminals: (a) (b) a-b b-c

Find the Thevenin equivalent of the circuit in Fig. 4.112 as seen by looking into terminals a and b.

Using Fig. 4.113, design a problem to help other students better understand Norton equivalent circuits.

Obtain the Thevenin and Norton equivalent circuits of the circuit in Fig. 4.114 with respect to terminals a and b.

Determine the Norton equivalent at terminals a-b for the circuit in Fig. 4.115.

Find the Norton equivalent looking into terminals of the circuit in Fig. 4.102. Let , I 3 A, , , and .

Obtain the Norton equivalent of the circuit in Fig. 4.116 to the left of terminals Use the result to find current i.

Given the circuit in Fig. 4.117, obtain the Norton equivalent as viewed from terminals: (a) a-b (b) c-d

For the transistor model in Fig. 4.118, obtain the Thevenin equivalent at terminals a-b.

Find the Norton equivalent at terminals of the circuit in Fig. 4.119.

Find the Thevenin equivalent between terminals of the circuit in Fig. 4.120.

Obtain the Norton equivalent at terminals of the circuit in Fig. 4.121.

Use Nortons theorem to find in the circuit of Fig. 4.122.

Obtain the Thevenin and Norton equivalent circuits at terminals for the circuit in Fig. 4.123.

The network in Fig. 4.124 models a bipolar transistor common-emitter amplifier connected to a load. Find the Thevenin resistance seen by the load.

Determine the Thevenin and Norton equivalents at terminals of the circuit in Fig. 4.125.

For the circuit in Fig. 4.126, find the Thevenin and Norton equivalent circuits at terminals a-b.

Obtain the Thevenin and Norton equivalent circuits at terminals of the circuit in Fig. 4.127.

Find the Thevenin equivalent of the circuit in Fig. 4.128.

Find the Norton equivalent for the circuit in Fig. 4.129.

Obtain the Thevenin equivalent seen at terminals of the circuit in Fig. 4.130.

For the circuit shown in Fig. 4.131, determine the relationship between and I0 V .

Find the maximum power that can be delivered to the resistor R in the circuit of Fig. 4.132.

The variable resistor R in Fig. 4.133 is adjusted until it absorbs the maximum power from the circuit. (a) Calculate the value of R for maximum power. (b) Determine the maximum power absorbed by R.

Compute the value of R that results in maximum power transfer to the 10- resistor in Fig. 4.134. Find the maximum power.

Find the maximum power transferred to resistor R in the circuit of Fig. 4.135.

Determine the maximum power delivered to the variable resistor R shown in the circuit of Fig. 4.136.

For the circuit in Fig. 4.137, what resistor connected across terminals will absorb maximum power from the circuit? What is that power?

(a) For the circuit in Fig. 4.138, obtain the Thevenin equivalent at terminals (b) Calculate the current in (c) Find for maximum power deliverable to (d) Determine that maximum power.

Determine the maximum power that can be delivered to the variable resistor R in the circuit of Fig. 4.139.

For the bridge circuit shown in Fig. 4.140, find the load for maximum power transfer and the maximum power absorbed by the load.

For the circuit in Fig. 4.141, determine the value of R such that the maximum power delivered to the load is 3 mW.

Solve Prob. 4.34 using PSpice or MultiSim. Let , , , , and .

Use PSpice or MultiSim to solve Prob. 4.44.

Use PSpice or MultiSim to solve Prob. 4.52.

Obtain the Thevenin equivalent of the circuit in Fig. 4.123 using PSpice or MultiSim. R3 20 V 40 V I

Use PSpice or MultiSim to find the Thevenin equivalent circuit at terminals of the circuit in Fig. 4.125.

For the circuit in Fig. 4.126, use PSpice or MultiSim to find the Thevenin equivalent at terminals Section

A battery has a short-circuit current of 20 A and an open-circuit voltage of 12 V. If the battery is connected to an electric bulb of resistance calculate the power dissipated by the bulb.

The following results were obtained from measurements taken between the two terminals of a resistive network. Terminal Voltage 12 V 0 V Terminal Current 0 A 1.5 A Find the Thevenin equivalent of the network.

When connected to a 4- resistor, a battery has a terminal voltage of 10.8 V but produces 12 V on an open circuit. Determine the Thevenin equivalent circuit for the battery.

The Thevenin equivalent at terminals of the linear network shown in Fig. 4.142 is to be determined by measurement. When a 10-k resistor is connected to terminals a-b, the voltage is measured as 6 V. When a 30-k resistor is connected to the terminals, is measured as 12 V. Determine: (a) the Thevenin equivalent at terminals a-b, (b) when a 20-k resistor is connected to terminals a-b. Vab Vab Vab a-b 2 , a-b.

A black box with a circuit in it is connected to a variable resistor. An ideal ammeter (with zero resistance) and an ideal voltmeter (with infinite resistance) are used to measure current and voltage as shown in Fig. 4.143. The results are shown in the table on the next page. (a) Find i when (b) Determine the maximum power from the box. R() V(V) i(A) 2 3 1.5 8 8 1.0 14 10.5 0.75

A transducer is modeled with a current source and a parallel resistance The current at the terminals of the source is measured to be 9.975 mA when an ammeter with an internal resistance of is used. (a) If adding a 2-k resistor across the source terminals causes the ammeter reading to fall to 9.876 mA, calculate and (b) What will the ammeter reading be if the resistance between the source terminals is changed to 4 k ?

Consider the circuit in Fig. 4.144. An ammeter with internal resistance is inserted between A and B to measure Determine the reading of the ammeter if: (a) (b) (Hint: Find the Thevenin equivalent circuit at terminals ) a-b

Consider the circuit in Fig. 4.145. (a) Replace the resistor by a zero resistance ammeter and determine the ammeter reading. (b) To verify the reciprocity theorem, interchange the ammeter and the 12-V source and determine the ammeter reading again.

The Wheatstone bridge circuit shown in Fig. 4.146 is used to measure the resistance of a strain gauge. The adjustable resistor has a linear taper with a maximum value of 100 If the resistance of the strain gauge is found to be what fraction of the full slider travel is the slider when the bridge is balanced?

(a) In the Wheatstone bridge circuit of Fig. 4.147, select the values of and such that the bridge can measure in the range of 010 R . x R1 R3 R3 Rx R1 V + G 50 Figure 4.147 For Prob. 4.91. (b) Repeat for the range of 0100 *

Consider the bridge circuit of Fig. 4.148. Is the bridge balanced? If the 10-k resistor is replaced by an 18-k resistor, what resistor connected between terminals absorbs the maximum power? What is this power?

The circuit in Fig. 4.149 models a common-emitter transistor amplifier. Find using source transformation.

An attenuator is an interface circuit that reduces the voltage level without changing the output resistance. (a) By specifying and of the interface circuit in Fig. 4.150, design an attenuator that will meet the following requirements: (b) Using the interface designed in part (a), calculate the current through a load of when Vg 12 V.

A dc voltmeter with a sensitivity of is used to find the Thevenin equivalent of a linear network. Readings on two scales are as follows: (a) 010 V scale: 4 V (b) 050 V scale: 5 V Obtain the Thevenin voltage and the Thevenin resistance of the network.

A resistance array is connected to a load resistor R and a 9-V battery as shown in Fig. 4.151. (a) Find the value of R such that (b) Calculate the value of R that will draw the maximum current. What is the maximum current?

A common-emitter amplifier circuit is shown in Fig. 4.152. Obtain the Thevenin equivalent to the left of points B and E.

For Practice Prob. 4.18, determine the current through the 40- resistor and the power dissipated by the resistor.