BASIC CONCEPTS
The following 75 questions concern basic units, definitions, laws, and
relations between important circuit quantities. In this version of the exam, the
first choice is always the correct one. In the actual exam, the correct choice
could be in any position, and there may be other changes to the choices. You can
always assume that numerical values for the resistance of resistors, inductance
of inductors and capacitance of capacitors are positive.
1. Charge is measured in
 coulombs
 volts
 amperes
 watts
 joules
2. Current is measured in
 amperes
 volts
 coulombs
 watts
 joules
3. Power is measured in
 watts
 volts
 coulombs
 amperes
 joules
4. Energy is measured in
 joules
 volts
 coulombs
 amperes
 watts
5. Resistance is measured in
 ohms
 henrys
 farads
 watts
 joules
6. Inductance is measured in
 henrys
 ohms
 farads
 watts
 joules
7. Capacitance is measured in
 farads
 henrys
 ohms
 watts
 joules
8. The current i through a capacitor and the charge
q that it holds are related by
 i = dq/dt
 q = di/dt
 q = 0.5 i^{2}
 i = 0.5 q^{2}
 q i = 1
9. The magnetic flux linkage l in an inductor and the voltage v across its terminals are
related by
 v = dl/dt
 l = dv/dt
 v = 0.5 l^{2}
 l = 0.5 v^{2}
 v l = 1
10. Kirchhoff's Voltage Law (KVL) can be stated as
 The sum of the voltage drops around any closed path is zero
 The sum of the voltages at all the nodes is zero
 The sum of the voltages across all the elements equals the sum of the
currents through all the elements
 The voltage across an element is proportional to the current through the
element
 The sum of the voltages into a node is equal to the sum of the voltages
out of the node
11. Kirchhoff's Voltage Law (KVL) can be stated as
 The voltage rise from Node a to Node b is the same for every path from a
to b
 The voltage rise from Node a to Node b is zero if Node b is a ground node
 The total voltage into a node equals the total voltage out of a node
 The voltage at Node a with Node b grounded is the same as the voltage at
Node b with Node a grounded
 The voltage between any two nodes is independent of the total current
flowing in the network
12. Kirchhoff's Current Law (KCL) can be stated as
 The sum of the currents flowing into any node is zero
 The sum of the currents flowing around any closed loop is zero
 The sum of the currents through all elements equals the sum of the
voltages across the elements
 The current through an element is proportional to the voltage across the
element
 The sum of the currents flowing clockwise around any mesh is equal to the
sum of the currents flowing counterclockwise around the same mesh
13. Kirchhoff's Current Law (KCL) can be stated as
 The sum of the currents entering a node equals the sum of the currents
leaving the node
 The sum of the currents entering a node equals the sum of the currents
entering the ground node
 The current flowing around any mesh is independent of the voltage sources
in that mesh
 The sum of the currents flowing around a mesh is zero
 The sum of the currents flowing through any element is equal to the
voltage dropped across that element
14. When two or more circuit elements are connected
in series
 the currents flowing through them are the same
 the voltages across them are the same
 the powers dissipated in them are the same
 the energies stored in them are the same
 the flux linkages produced by them are the same
15. When two or more circuit elements are connected
in parallel
 the voltages across them are the same
 the currents flowing through them are the same
 the powers dissipated in them are the same
 the energies stored in them are the same
 the flux linkages produced by them are the same
16. The voltage v(t) across an independent voltage
source
 does not depend on the current i(t) through the source
 is proportional to the current i(t) through the source
 does not depend on time t
 cannot provide power to an external circuit
 always provides power to an external circuit








17. The current i(t) through an independent current
source
 does not depend on the voltage v(t) across the source
 is proportional to the voltage v(t) across the source
 does not depend on time t
 cannot provide power to an external circuit
 always provides power to an external circuit








18. The voltage v_{c} for the dependent
source shown
 is proportional to the voltage v_{x} somewhere else in the
circuit
 is proportional to the current i through the source
 cannot provide power to an external circuit
 always provides power to an external circuit
 is never negative








19. The voltage v_{c} for the dependent
source shown
 is proportional to the current i_{x} somewhere else in the
circuit
 is proportional to the current i through the source
 cannot provide power to an external circuit
 always provides power to an external circuit
 is never negative








20. The current i_{c} for the dependent
source shown
 is proportional to the current i_{x} somewhere else in the
circuit
 is proportional to the voltage v across the source
 cannot provide power to an external circuit
 always provides power to an external circuit
 is never negative








21. The current i_{c} for the dependent
source shown
 is proportional to the voltage v_{x} somewhere else in the
circuit
 is proportional to the voltage v across the source
 cannot provide power to an external circuit
 always provides power to an external circuit
 is never negative








22. The openloop voltage gain of an ideal
operational amplifier is
 infinite
 unity
 zero
 inverting
 noninverting








23. The current flowing into either input of an
ideal operational amplifier is
 zero
 unity
 infinite
 inverting
 noninverting








24. The current i_{0} flowing out of an
ideal operational amplifier is
 found by writing a KCL equation at the output node
 equal to the sum of the currents i_{1} and i_{2}
 zero, if the amplifier is ideal
 never negative
 determined by the largest resistor in the circuit








25. The circuit shown is called
 a voltage follower
 an inverting amplifier
 a fullwave rectifier
 an integrator
 a differentiator








26. The circuit shown is called
 a noninverting amplifier
 an inverting amplifier
 a fullwave rectifier
 an integrator
 a differentiator








27. The circuit shown is called
 an inverting amplifier
 a noninverting amplifier
 a fullwave rectifier
 an integrator
 a differentiator








28. Ohm's Law is
 v = R i
 v = L di/dt
 p = i^{2} R
 p = v i
 i = C dv/dt
29. The resistance R and the conductance G of a
resistor are related by
 G = 1 / R
 G = 2 p R
 G = 2 p / R
 R + G = 1
 G = e^{R}
30. The voltage v across an inductor and the current
i through it are related by
 v = L di/dt
 i = L dv/dt
 v = L i
 i = L v
 dv/dt = L i








31. The voltage v across a capacitor and the current
i through it are related by
 i = C dv/dt
 v = C di/dt
 i = C v
 v = C i
 di/dt = C v








32. The relationship between power p and energy w is
 p = dw/dt
 w = dp/dt
 p = w^{2}
 w = p^{2}
 p = 1 / w
33. The instantaneous power p(t) flowing into a
circuit element
 is given by p = v i
 is given by p = v / i
 is given by p = i / v
 can never be negative
 can never be positive








34. The energy w(t) transferred into a circuit
element
 is given by
 is given by w = v i
 is given by w = v / i
 is given by w = i / v
 is zero if t is negative








35. The power dissipated by a resistor is
 p = i^{2} R
 p = v^{2} R
 p = v i R
 p = v i / R
 p = i^{2} / R








36. The power dissipated by a resistor is
 p = v^{2} / R
 p = v^{2} R
 p = v i R
 p = v i / R
 p = i^{2} / R








37. The power dissipated by a resistor
 cannot be negative
 is called the conductance
 is measured in joules
 is equal to the power that it generates
 is purely imaginary
38. The energy stored in an inductor L is given by
 0.5 L i^{2}
 L di/dt
 v i
 0.5 L dv/dt
 0.5 v^{2} / L








39. The energy stored in a capacitor C is
 0.5 C v^{2}
 C v
 C dv/dt
 0.5 C di/dt
 0.5 i^{2} / C








40. If a stable linear network is driven by a
sinusoidal source, in steady state
 every voltage and every current has the same frequency
 every voltage and every current has the same amplitude
 every voltage and every current has the same phase
 all voltages and currents are constant
 the power absorbed by the resistive elements is equal to the power
provided by the reactive elements
41. The angular frequency w
(in rad/s) is related to the frequency f (in Hz) by
 w = 2 p f
 f = 2 p w
 w = 1 / f
 w = 2 p / f
 w + f = 1
42. If a voltage is given by v(t) = V_{m}
cos(w t + f), the
corresponding phasor voltage V is
 V = V_{m} e^{j f}
 V = V_{m} e^{j w t}
 V = Re{ V_{m} e^{j(w t + f)} }
 V = 0.5(V_{m} + V_{m} ^{*})
 V = j w V_{m}
43. If the phasor current for a frequency w is given by I = I_{m} e^{j f} , the corresponding timedomain current i(t) is
 i(t) = I_{m} cos(w t + f)
 i(t) = I_{m} e^{j(w t + f)}
 i(t) = I_{m} e^{ f t} cos(w t)
 i(t) = I_{m} e^{ w t} cos(f t)
 i(t) = I_{m} e^{ jw t} cos(f t)
44. If a phasor voltage V is written in polar
form as V = V_{m} e^{j f}
 V_{m} is called the amplitude
 V_{m} is called the admittance
 f is called the frequency
 f is called the susceptance
 V_{m} is purely imaginary
45. If a phasor current I is written in polar
form as I = I_{m} e^{j f}
 f is called the phase angle
 f is called the frequency
 I_{m} is called the conductance
 I_{m} is called the admittance
 I_{m} is purely imaginary
46. The relationship between the phasor voltage
V, the phasor current I and the impedance Z is
 V = Z I
 I = Z V
 Z = V I^{*}
 Z = V + I
 Z = V I cos q
47. If I = I_{m} e^{j f} and Z = Z_{m} e^{j q} then the product Z I is given by
 Z_{m} I_{m} e^{j(q+f)}
 Z_{m} I_{m} e^{j(qf)}
 Z_{m} I_{m} e^{j(qf)}
 (Z_{m} + I_{m}) e^{j(q+f)}
 (Z_{m} + I_{m} ) e^{j(qf)}
48. The impedance Z and the admittance Y are related
by
 Y = 1 / Z
 Y = 2 p Z
 Y = 2 p / Z
 Y + Z = 1
 Y = e^{j w Z}
49. The impedance Z and the admittance Y are related
by
 Y Z = 1
 Z = 2 p Y
 Z = 2 p / Y
 Z + Y = 1
 Z = e^{j w Y}
50. If an impedance Z is written in rectangular form
as Z = R +j X,
 X is called the reactance
 X cannot be positive
 X cannot be negative
 X must become infinite at high frequencies
 R and X are measured in different units
51. The impedance of an inductor L at angular
frequency w is
 Z = j w L
 Z = 1 / j w L
 Z = 0.5 w ^{2}
 Z = w L
 Z = 1 / w L
52. The impedance of an inductor is
 purely imaginary
 infinite at DC
 constant
 a sinusoidal function of frequency
 indeterminate
53. The reactance of an inductor L at angular
frequency w is
 X = w L
 X = w L
 X = 1 / w L
 X =  1 / w L
 X = j w L
54. The reactance of an inductor
 is never negative
 is never positive
 decreases in magnitude as frequency increases
 decreases in magnitude as the inductance increases
 is equal to the energy stored in the inductor
55. The impedance of a capacitor C at angular
frequency w is
 Z = 1 / j w C
 Z = j w C
 Z = 0.5 w^{2} C
 Z = w C
 Z = 1 / w C
56. The impedance of a capacitor is
 purely imaginary
 zero at DC
 constant
 a sinusoidal function of frequency
 indeterminate
57. The reactance of a capacitor C at angular
frequency w is
 X =  1 / w C
 X = 1 / w C
 X = w C
 X = w C
 X = 1 / j w C
58. The reactance of a capacitor
 is never positive
 is never negative
 increases in magnitude as frequency increases
 increases as the capacitance increases
 is equal to the energy stored in the capacitor
59. The impedance of a resistor R at angular
frequency w is
 Z = R
 Z = j R
 Z = j w R
 Z = 1 / R
 Z =1 / j w R
60. At very high frequencies, an inductor acts like
 an open circuit
 a short circuit
 a voltage source
 a capacitor
 an operational amplifier
61. At very low frequencies, an inductor acts like
 a short circuit
 an open circuit
 a current source
 a capacitor
 an operational amplifier
62. At very high frequencies, a capacitor acts like
 a short circuit
 an open circuit
 a current source
 an inductor
 an operational amplifier
63. At very low frequencies, a capacitor acts like
 an open circuit
 a short circuit
 a voltage source
 an inductor
 an operational amplifier
64. The equivalent impedance for three impedances
connected in series is
65. The equivalent impedance for three impedances
connected in parallel is
66. The circuit shown is called
 a voltage divider
 a current divider
 an inverting amplifier
 a noninverting amplifier
 a fullwave rectifier








67. For the circuit shown
68. The circuit shown is called
 a current divider
 a voltage divider
 an inverting amplifier
 a noninverting amplifier
 a fullwave rectifier








69. For the circuit shown,
70. An inactive or "dead" voltage source is
equivalent to
 a short circuit
 an open circuit
 an ideal inductor
 an ideal capacitor
 an active or "live" current source
71. An inactive or "dead" current source is
equivalent to
 an open circuit
 a short circuit
 an ideal inductor
 an ideal capacitor
 an active or "live" voltage source
72. The Thevenin equivalent impedance can be
obtained by
 applying a test source with all independent sources dead
 applying a test source with all dependent sources dead
 short circuiting all inductors and open circuiting all capacitors
 open circuiting all inductors and short circuiting all capacitors
 replacing all inductors by capacitors and all capacitors by inductors
73. The Thevenin equivalent voltage can be obtained
by
 solving for the opencircuit voltage
 solving for shortcircuit voltage
 solving for the opencircuit current
 short circuiting all inductors and open circuiting all capacitors
 open circuiting all inductors and short circuiting all capacitors
74. The Norton equivalent current can be obtained by
 solving for the shortcircuit current
 solving for the opencircuit current
 solving for the shortcircuit voltage
 short circuiting all inductors and open circuiting all capacitors
 open circuiting all inductors and short circuiting all capacitors
75. The impedances in the Thevenin and Norton
equivalent circuits
 are equal
 are complex conjugates of one another
 are negatives of one another
 are undefined when w is zero
 are undefined when w is infinite
End of Questions on Basic Concepts