Chap#15 Alternating Current

Question 1

In L.C.R series A.C. circuit, the phase angle between current and voltage is:

Answer 1

Any angle between 0 and +- π/2

Question 2

In an A.C. circuit, a resistance of R ohm is connected in series with an inductance L. If phase angle between voltage and current be 45°, the value of inductive reactance will be:

Answer 2

R

Question 3

A 220V, 50 Hz A.C. source is connected to an inductance of 0.2 H and a resistance of 20 ohm in series. What is the current in the circuit?

Answer 3

3.33 A

Question 4

A capacitor acts as an infinte resistance for:

Answer 4

DC

Question 5

An ideal choke (used along with fluorescent tube) would be:

Answer 5

A pure inductor

Question 6

The peak voltage in a 220 volt A.C. supply is nearly:

Answer 6

311 volt

Question 7

In a capacitive circuit:

Answer 7

Current leads voltage by phase of π/2

Question 8

The reactance of a coil when used in the domestic A.C. power supply (220 volts, 50 cycles per second) is 50 ohms. The inductance of the coil is nearly:

Answer 8

0.16 Henry

Question 9

Energy is stored in the choke coil in the form of:

Answer 9

Magnetic Energy