Unit 3
Inductor has an inductance if 0.8 H and is connected to a 120V, 60 Hz. Line. How much current will flow in this circuit if the where resistance of the inductor is negligible?
0.398 A
Three inductors are connected in parallel. Inductor 1 = 2.5 H. Inductor 2 = 1.8 H. Inductor 3 = 1.2 H. What is the total inductance?
0.559 H
Three inductors are connected in series. Inductor one = 0.6 H. Inductor two = 0.4 H. Inductor 3 = 0.5 H. What is the total inductance?
1.5 H
In a pure inductive circuit, the current lags voltage by?
90 degrees
When inductors are connected in series, the total inductance is the circuit (Lt) equals the sum of what?
All inductors
What does the schematic symbol used to represent an inductor depicts?
Coil of wire
If the values of all the inductors are the same, total inductance can be found using the formula Lt=N/L
False
In a pure inductive circuit, true power, or wattage, is equal to the product of the voltage and current. In a pure resistive circuit no true power is produced.
False
Reactance is caused by inductance, and is called reactive inductance.
False
Some amount of inductance is present in all ac circuits because the magnetic field doesn't change.
False
A total current limiting effect is called what? And represented by what letter?
Impedance, Z
In an inductor, what can be computed if the resistance of the wire in the in the coil and the amount of circuit current is known?
Induced voltage
What is an induced voltage and is proportional to the three factors that determine induced voltage?
Inductive reactance
Formula to find total inductance of two parallel inductors is LT =
L1 • L2 / L1 + L2
Assume an inductor with a negligible resistance is connected to a 36V, 400 Hz line. If the circuit has a current flow of 0.2 A, the inductance of the inductor is 0.0716 H.
True
Since induced voltage is always in opposition to applied voltage, the applied voltage must overcome the induced voltage before current can flow through the circuit.
True
The amount of induced voltage in an inductor can be computed if the resistance of the wire in the coil and the amount of circuit is known.
True
Ohm's Law
V=IR
An electrical measurement used to measure the reactive power in a pure inductive circuit is called what?
VARs
What letter is reactance symbolized with?
X