1. What is the sum of 130 + j180 and 5 - j30?
A. (1352) + (j150)2
B. 135 + j210
C. 135 + j150
D. 135 - j150
2. Which of the following is a correct equation?
A. Q = fr - bandwidth
B. Q = fr x bandwidth
C. Q = fr / bandwidth
D. Q = fr + bandwidth
3. Which one of the following expresses an impedance of 50 OHMS with no resistance component in rectangular coordinates?
A. 50 + j0 OHMS
B. 0 + j50 OHMS
C. 50 OHMS
D. 100 OHMS
4. When one vibrating body sets a second body into vibration at the same natural frequency it's called
A. natural sympathy.
B. mutual sympathy.
C. sympathetic vibration.
D. sympathy.
5. Which of the following is a parasitic suppressor?
A. Back-to-back transistors
B. A long piece of wire
C. Ferrite bead
D. Bead ledge
6. At the resonant frequency, the impedance of a parallel LC circuit is
A. minimum.
B. equal to XL-XC.
C. equal to XL+Xc.
D. maximum.
7. Which of the following is a measure of how sharply a basic series resonant circuit tunes?
A. Xc
B. XL
C. XL-Xc
D. Q
8. The reciprocal of capacitor Q is
A. bandwidth
B. sus ceptance.
C. dissipation factor.
D. gain.
9. The bandwidth of a series-tuned circuit is that range of frequencies between where the voltage is of the maximum voltage.
A. 33.3%
B. 75.2%
C. 70.7%
D. 50.5%
10. Tuning forks have been used as timing oscillators in
A. automobiles.
B. watches.
C. jet engines.
D. broadcast transmitters.
11. You can lower the resonant frequency of a series-tuned RLC circuit by
A. increasing R.
B. increasing L.
C. decreasing C.
D. decreasing R.
12. In a series RLC circuit, the current is
A. equal to voltage divided by inductive reactance.
B. equal to inductive reactance divided by resistance.
C. maximum at the resonant frequency.
D. minimum at the resonant frequency.
13. Parasitic oscillations can be caused by
A. very low inductance in an RLC circuit.
B. very low capacitance in an RLC circuit.
C. very high resistance in an RLC circuit.
D. distributed components.
14. Which of the following is correct regarding a right triangle?
A. Sine of angle = hypotenuse/opposite side
B. Sine of angle = adjacent side/opposite side
C. Sine of angle = opposite side/hypotenuse
D. Sine of angle = opposite side/adjacent side
15. You can increase the resonant frequency of a series-tuned RLC circuit by
A. decreasing C.
B. increasing R.
C. increasing L.
D. decreasing R.
16. Which of the following is a waveform that has no harmonic frequencies?
A. Sawtooth
B. Sine
C. Triangular
D. Square
17. In a certain tuned series RLC circuit XL = XC. The impedance of that circuit is equal to
A. XL + XC
B. XL - XC.
C. R.
D. R2.
18. You strike one tuning fork and another nearby tuning fork starts to vibrate. In order for this to happen
A. they must be resonant to be the same frequency.
B. both tuning forks must be electrically connected.
C. both tuning forks must be in a vacuum.
D. there must be a feedback circuit between them.
19. 40 ∠ 40° x 30 ∠ 20° equals
A. 70 ∠ 80°.
B. 70 ∠ 800°.
C. 1200 ∠ 60°.
D. 0.75 ∠ 60°.
20. Which of the following can be used to offer a higher impedance to all frequencies except the resonant frequency?
A. Series LC circuit
B. RC time constant circuit
C. RL time constant circuit
D. Parallel LC circuit
21. An inductor that has an inductive reactance of 12 OHMS and a DC resistance of 1 OHM has a Q of
A. 12/1.
B. 5/12
C. 12/2.
D. 1/12.
22. In a series-resonant RLC circuit, the voltage across L is ____ with the voltage across C.
A. 180° out of phase
B. 270° out of phase
C. in phase
D. 90° out of phase
23. Which of the following is equal to the angular velocity (ω)?
A. ω = 2ΠL
B. ω = 2Πf
C. ω = 2ΠC
D. ω = 2ΠR
24. In a purely capacitive circuit with an applied sine wave voltage, the voltage
A. will lag the current.
B. will be in phase with the current.
C. must be DC.
D. will lead the current.
25. The resonant frequency curve of a series RLC circuit will indicate broader tuning at the resonant frequency if you increase the
A. capacitance of the circuit.
B. induction of the circuit.
C. Q of the circuit.
D. resistance of the circuit.