5) When the frequency of an a.c. circuit containing resistance and inductance is increased, the current (a) decreases (b) increases (c) stays the same 6) When the frequency of an a.c. circuit containing resistance and capacitance is decreased, the current (a) decreases (b) increases (c) stays the same 7) In a series a.c. circuit the voltage across a pure inductance is 12 V and the voltage across a pure resistance is 5 V. The supply voltage is (a) 13 V (b) 17 V (c) 7 V (d) 2.4 V 8) The impedance of a coil, which has a resistance of X ohms and an inductance of Y henrys, connected across a supply of frequency K Hz, is (a) 2n KY (b) X + Y (c) √X²+Y2 (d) √X² + (2πKY)²

5) When the frequency of an a.c. circuit containing resistance and inductance is increased, the current (a) decreases (b) increases (c) stays the same 6) When the frequency of an a.c. circuit containing resistance and capacitance is decreased, the current (a) decreases (b) increases (c) stays the same 7) In a series a.c. circuit the voltage across a pure inductance is 12 V and the voltage across a pure resistance is 5 V. The supply voltage is (a) 13 V (b) 17 V (c) 7 V (d) 2.4 V 8) The impedance of a coil, which has a resistance of X ohms and an inductance of Y henrys, connected across a supply of frequency K Hz, is (a) 2n KY (b) X + Y (c) √X²+Y2 (d) √X² + (2πKY)²

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter20: Capacitance In Ac Circuits

Section: Chapter Questions

Problem 2PA: You are working in an industrial plant. You have been instructed to double the capacitance connected...

See similar textbooks

Similar questions

Three capacitors having capacitance values of 20F,40F, and 50F are connected in parallel to a 60 - Hz power line. An ammeter indicates a circuit current of 8.6 amperes. How much current is flowing through the 40F capacitor?
A 15-F AC capacitor is connected in series with a 50 resistor. The capacitor has a voltage rating of 600 WVDC. The capacitor and resistor are connected to a 480-V, 60-Hz circuit. Is the voltage rating of the capacitor sufficient for this connection?
In reference to the load, how are capacitors connected to help prevent voltage spikes and surges? Are capacitors connected in parallel or in series with the load?
You find that a 25-F capacitor connected to 480 VAC is defective. The storeroom has no capacitors with a 480-VAC rating. However, you find two capacitors rated at 50 F and 370 VAC. Can these two capacitors be connected in such a manner that they can replace the defective capacitor? If yes, explain how they are connected and why the capacitors will not be damaged by the lower voltage rating. If no, explain why they cannot be used without damaging the capacitor.
You are working in an industrial plant. You have been instructed to double the capacitance connected to a machine. The markings on the capacitor, however, are not visible. The capacitor is connected to 560 volts and an ammeter indicates a current of 6 amperes flowing to the capacitor. What size capacitor should be connected in parallel with the existing capacitor? What is the minimum AC voltage rating of the new capacitor? What is the minimum DC voltage rating of the new capacitor? What is the minimum KVAR size that can be used in this installation?
An RC series circuit is connected to a 120-V, 60-Hz power source. The resistor is 25 and has a voltage drop of 65 volts. What is the capacitance of the capacitor?
How many degrees are the current and voltage out of phase in a pure capacitive circuit?
6) When the frequency of an a.c. circuit containing resistance and capacitance is decreased, the current (a) decreases (b) increases (c) stays the same 7) In a series a.c. circuit the voltage across a pure inductance is 12 V and the voltage across a pure resistance is 5 V. The supply voltage is (a) 13 V (b) 17 V (c) 7 V (d) 2.4 V 8) The impedance of a coil, which has a resistance of X ohms and an inductance of Y henrys, connected across a supply of frequency K Hz, is (a) 2π Κ Υ (b) X + Y (c) √x² + y² (d) √X² + (2nKY)² 9) When a capacitor is connected to an a.c. supply the current (a) leads the voltage by 180° (c) leads the voltage by 1/2 rad (b) is in phase with the voltage (d) lags the voltage by 90° 10) In an R-L-C series a.c. circuit a current of 5 A flows when the supply voltage is 100 V. The phase angle between current and voltage is 60° lagging. Which of the following statements is false? (a) The circuit is effectively inductive (c) The equivalent circuit reactance is 25 2 (b)…
6) When the frequency of an a.c. circuit containing resistance and capacitance is decreased, the current (a) decreases (b) increases (c) stays the same 7) In a series a.c. circuit the voltage across a pure inductance is 12 V and the voltage across a pure resistance is 5 V. The supply voltage is (a) 13 V (b) 17 V (c) 7 V (d) 2.4 V 8) The impedance of a coil, which has a resistance of X ohms and an inductance of Y henrys, connected across a supply of frequency K Hz, is (a) 2π Κ Υ (b) X + Y (c) √x² + y² (d) X² + (2nKY)²
A utility company plans to connected a total of 20uF of capacitance to a 7,200 volt line. To make this connection, four capacitors will be connected in series. What is the capacitance of each capacitor?
Identify which of the following statement is true, if two capacitances of the same value are present in the circuit, the equivalent capacitancecan be half the value of given capacitance. a. If the capacitances are connected in series. b. None of the given option c. It is not possible d. If the capacitances are connected in parallel.
1.Enumerate five formulas for series-parallel connected inductances and draw the circuit. 2.Enumerate five formulas for parallel-series connected inductances and draw the circuit.