# Extra Class Exam Question Pool

effective 7/01/2008 thru 6/30/2012

 Show: Unseen questions Weak questions Review questions Learned questions Incorrect answer choices

E5C: Impedance plots and coordinate systems: plotting impedances in polar coordinates; rectangular coordinate

E5C01: In polar coordinates, what is the impedance of a network consisting of a 100-ohm-reactance inductor in series with a 100-ohm resistor?

141 ohms at an angle of 45 degrees

121 ohms at an angle of 35 degrees

161 ohms at an angle of 55 degrees

181 ohms at an angle of 65 degrees

E5C02: In polar coordinates, what is the impedance of a network consisting of a 100-ohm-reactance inductor, a 100-ohm-reactance capacitor, and a 100-ohm resistor, all connected in series?

100 ohms at an angle of 0 degrees

100 ohms at an angle of 90 degrees

10 ohms at an angle of 0 degrees

10 ohms at an angle of 90 degrees

E5C03: In polar coordinates, what is the impedance of a network consisting of a 300-ohm-reactance capacitor, a 600-ohm-reactance inductor, and a 400-ohm resistor, all connected in series?

500 ohms at an angle of 37 degrees

900 ohms at an angle of 53 degrees

400 ohms at an angle of 0 degrees

1300 ohms at an angle of 180 degrees

E5C04: In polar coordinates, what is the impedance of a network consisting of a 400-ohm-reactance capacitor in series with a 300-ohm resistor?

500 ohms at an angle of -53.1 degrees

240 ohms at an angle of 36.9 degrees

240 ohms at an angle of -36.9 degrees

500 ohms at an angle of 53.1 degrees

E5C05: In polar coordinates, what is the impedance of a network consisting of a 400-ohm-reactance inductor in parallel with a 300-ohm resistor?

240 ohms at an angle of 36.9 degrees

240 ohms at an angle of -36.9 degrees

500 ohms at an angle of 53.1 degrees

500 ohms at an angle of -53.1 degrees

E5C06: In polar coordinates, what is the impedance of a network consisting of a 100-ohm-reactance capacitor in series with a 100-ohm resistor?

141 ohms at an angle of -45 degrees

121 ohms at an angle of -25 degrees

191 ohms at an angle of -85 degrees

161 ohms at an angle of -65 degrees

E5C07: In polar coordinates, what is the impedance of a network comprised of a 100-ohm-reactance capacitor in parallel with a 100-ohm resistor?

71 ohms at an angle of -45 degrees

31 ohms at an angle of -15 degrees

51 ohms at an angle of -25 degrees

91 ohms at an angle of -65 degrees

E5C08: In polar coordinates, what is the impedance of a network comprised of a 300-ohm-reactance inductor in series with a 400-ohm resistor?

500 ohms at an angle of 37 degrees

400 ohms at an angle of 27 degrees

500 ohms at an angle of 47 degrees

700 ohms at an angle of 57 degrees

E5C09: When using rectangular coordinates to graph the impedance of a circuit, what does the horizontal axis represent?

The voltage or current associated with the resistive component

The voltage or current associated with the reactive component

The sum of the reactive and resistive components

The difference between the resistive and reactive components

E5C10: When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

The voltage or current associated with the reactive component

The voltage or current associated with the resistive component

The sum of the reactive and resistive components

The difference between the resistive and reactive components

E5C11: What do the two numbers represent that are used to define a point on a graph using rectangular coordinates?

The coordinate values along the horizontal and vertical axes

The magnitude and phase of the point

The sine and cosine values

The tangent and cotangent values

E5C12: If you plot the impedance of a circuit using the rectangular coordinate system and find the impedance point falls on the right side of the graph on the horizontal line, what do you know about the circuit?

It is equivalent to a pure resistance

It has to be a direct current circuit

It contains resistance and capacitive reactance

It contains resistance and inductive reactance

E5C13: What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of an impedance?

Rectangular coordinates

Elliptical coordinates

E5C14: What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive and/or capacitive reactance?

Polar coordinates

Elliptical coordinates

E5C15: In polar coordinates, what is the impedance of a circuit of 100 -j100 ohms impedance?

141 ohms at an angle of -45 degrees

100 ohms at an angle of 45 degrees

100 ohms at an angle of -45 degrees

141 ohms at an angle of 45 degrees

E5C16: In polar coordinates, what is the impedance of a circuit that has an admittance of 7.09 millisiemens at 45 degrees?

141 ohms at an angle of -45 degrees

5.03 x 10 -E05 ohms at an angle of 45 degrees

19,900 ohms at an angle of -45 degrees

141 ohms at an angle of 45 degrees

E5C17: In rectangular coordinates, what is the impedance of a circuit that has an admittance of 5 millisiemens at -30 degrees?

173 + j100 ohms

173 - j100 ohms

200 + j100 ohms

200 - j100 ohms

E5C18: In polar coordinates, what is the impedance of a series circuit consisting of a resistance of 4 ohms, an inductive reactance of 4 ohms, and a capacitive reactance of 1 ohm?

5 ohms at an angle of 37 degrees

6.4 ohms at an angle of 53 degrees

5 ohms at an angle of 45 degrees

10 ohms at an angle of -51 degrees

E5C19: Which point on Figure E5-2 best represents that impedance of a series circuit consisting of a 400 ohm resistor and a 38 picofarad capacitor at 14 MHz?

Point 4

Point 2

Point 5

Point 6

E5C20: Which point in Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and an 18 microhenry inductor at 3.505 MHz?

Point 3

Point 1

Point 7

Point 8

E5C21: Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and a 19 picofarad capacitor at 21.200 MHz?

Point 1

Point 3

Point 7

Point 8

E5C22: In rectangular coordinates, what is the impedance of a network comprised of a 10-microhenry inductor in series with a 40-ohm resistor at 500 MHz?

40 + j31,400

40 - j31,400

31,400 + j40

31,400 - j40

E5C23: Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300-ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

Point 8

Point 1

Point 3

Point 5

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