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| 1 | XL and R are both measured in ohms and they can be added by simple arithmetic. |
 | A) | True |
| B) | False |
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| 2 | The phase angle for the voltage across XL is at 90° with respect to the current through L. |
| A) | True |
| B) | False |
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| 3 | A cosine wave has its maximum values at 0° and 180° and its minimum values at 90° and 270°. |
| A) | True |
| B) | False |
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| 4 | When sine wave variations of current produce an induced voltage, the voltage lags its current by exactly 90°. |
| A) | True |
| B) | False |
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| 5 | When a coil has series resistance, the current is limited by both XL and R. |
| A) | True |
| B) | False |
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| 6 | In a series RL circuit, I and IR have a phase angle of 90°. |
| A) | True |
| B) | False |
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| 7 | The resultant of the phasor addition of R and XL is their total opposition in henries, called reluctance. |
| A) | True |
| B) | False |
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| 8 | In phasor triangles for volts and ohms in a series circuit, the phasor for R, IR or VR is used as a reference at 180°. |
| A) | True |
| B) | False |
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| 9 | The tangent is a trigonometric function of any angle of a right triangle, equal to the ratio of the opposite side to the adjacent side of a triangle. |
| A) | True |
| B) | False |
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| 10 | A parallel circuit has different currents. |
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| 11 | In a series RL circuit, the voltage drops VRand VL are degrees out of phase. |
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| 12 | If the internal resistance of a coil is low, its Q is . |
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| 13 | An inductance in series with an external resistance used to prevent the ac signal voltage from developing any appreciable output across the resistance at the frequency of the source is called a(n) . |
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| 14 | The resultant of the phasor addition of R and XL is . |
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| 15 | In order to effective resistance for small rf coils, litz wire should be used. |
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| 16 | Typically, the lower the internal resistance of a coil, the higher its . |
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| 17 | For any inductor, the voltage remains constant if the rate of current change is constant. |
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| 18 | For a series RL circuit, when R is equal to or 10 times greater than XL |
| A) | ZT is approximately equal to zero ohms |
| B) | ZT is approximately equal to infinite ohms |
| C) | ZT is approximately equal to R |
| D) | ZT is approximately equal to XL |
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| 19 | What is the phase relationship between IR and VA in a parallel RL circuit? |
| A) | IR leads VA by 90° |
| B) | IR lags VA by 90° |
| C) | IR leads VA by 180° |
| D) | IR is in phase with VA |
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| 20 | When radio-frequency current tends to flow at the surface of a conductor at very high frequencies, with little current in the solid core at the center is referred to as |
| A) | coax current |
| B) | eddy current |
| C) | rf effect |
| D) | skin effect |
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| 21 | The factors that make the effective resistance of a coil more than its dc resistance do not include which of the following? |
| A) | skin effect |
| B) | eddy currents |
| C) | counter emf |
| D) | hysteresis |
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| 22 | Inductance has the useful characteristic of providing more ohms of reactance at |
| A) | lower frequencies |
| B) | higher frequencies |
| C) | resonant frequencies |
| D) | harmonic frequencies |
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| 23 | For any inductor, the induced voltage remains constant if |
| A) | the rate of current change is varied |
| B) | the rate of current change is constant |
| C) | it is part of a series circuit |
| D) | it is part of a parallel circuit |
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| 24 | In an RL circuit, as the frequency increases |
| A) | R increases |
| B) | R decreases |
| C) | XL increases |
| D) | XL decreases |
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| 25 | When sine-wave variations of current produce an induced voltage, the current |
| A) | lags its induced voltage by 90° |
| B) | leads its induced voltage by 90° |
| C) | lags its induced voltage by 180° |
| D) | lags its induced voltage by 45° |