Discussion
Home ‣ Electrical Engineering ‣ RC Circuits See What Others Are Saying!
- Question
A capacitor with 150 Ω of capacitive reactance is across an ac source. The impedance, expressed in polar form, is
Options- A. Z = 150
- B. Z = 150∠90°Ω
- C. Z = 150 ∠?90°Ω
- D. Z = 150∠180°Ω
- Correct Answer
- Z = 150 ∠?90°Ω
- 1. For a given wirewound core, an increase in current through the coil
Options- A. reverses the flux lines
- B. decreases the flux density
- C. increases the flux density
- D. causes no change in flux density Discuss
- 2. In a parallel RL circuit, there are 3 A rms in the resistive branch and 3 A rms in the inductive branch. The total rms current is
Options- A. 6 A
- B. 424 mA
- C. 4.24 A
- D. 42.4 A Discuss
- 3. What is the capacitance when Q = 60 µC and V = 12 V?
Options- A. 720 µF
- B. 5 µF
- C. 50 µF
- D. 12 µF Discuss
- 4. A step-down transformer has a turns ratio less than 1.
Options- A. True
- B. False Discuss
- 5. A Thevenin ac equivalent circuit always consists of an equivalent ac voltage source and an equivalent capacitance.
Options- A. True
- B. False Discuss
- 6. If a periodic pulse waveform has a pulse width and the time between pulses each equal to or greater than five time constants, the capacitor will
Options- A. partially charge and fully discharge during each period of the input waveform
- B. fully charge and partially discharge during each period of the input waveform
- C. fully charge and fully discharge during each period of the input waveform
- D. partially charge and partially discharge during each period of the input waveform Discuss
- 7. Referring this circuit, determine the maximum output voltage when a single pulse is applied as shown. The total resistance is 60 Ω.
Options- A. 2.73 V
- B. 27.33 V
- C. 30 V
- D. 2.67 V Discuss
- 8. Referring to Problem 7, how much will the capacitor charge if the pulse width is increased to 12 ms?
Options- A. 2.51 V
- B. 25.14 V
- C. 4.86 V
- D. 12.76 V Discuss
- 9. If the capacitor in an integrator becomes leaky,
Options- A. the time constant will be effectively reduced
- B. the waveshape of the output voltage across C is altered
- C. the amplitude of the output is reduced
- D. all of the above Discuss
- 10. The following resistors (one each) are connected in a series circuit: 470 Ω, 680 Ω, 1 kΩ, and 1.2 kΩ. The voltage source is 20 V. Current through the 680 Ω resistor is approximately
Options- A. 60 mA
- B. 30 mA
- C. 6 mA
- D. 300 mA Discuss
More questions
Correct Answer: increases the flux density
Correct Answer: 4.24 A
Correct Answer: 5 µF
Correct Answer: True
Explanation:
Ns/Np is known as the turns ratio.
In step down transformer the number of turns in secondary winding (Ns) will be less than the number of turns in primary (Np).
Therefore, the ratio will be less than 1 for step down transformer.
Ex: Np = 10, Ns = 5; Turns ratio = 5/10 = 0.5.
In step down transformer the number of turns in secondary winding (Ns) will be less than the number of turns in primary (Np).
Therefore, the ratio will be less than 1 for step down transformer.
Ex: Np = 10, Ns = 5; Turns ratio = 5/10 = 0.5.
Correct Answer: False
Correct Answer: fully charge and fully discharge during each period of the input waveform
Correct Answer: 27.33 V
Correct Answer: 25.14 V
Correct Answer: all of the above
Correct Answer: 6 mA
Comments
There are no comments.More in Electrical Engineering:
Programming
Copyright ©CuriousTab. All rights reserved.