Circuits Quiz for Lesson 6
When a steady direct current flows through a coil, the only opposition to the flow of current
is the resistance of the wire from which the coil is made. - ** VERIFIED ANSWERS
**✔✔True
Alternating current flowing through a coil is opposed by two factors, resistance (R) and
inductive reactance (XL). - ** VERIFIED ANSWERS **✔✔True
? is the induction of voltage or CEMF that opposes the current flow in a coil. - ** VERIFIED
ANSWERS **✔✔Inductive Reactance
The total current-limiting effect of the inductor is a combination of the inductive reactance
and resistance of the inductor. - ** VERIFIED ANSWERS **✔✔True
The total current-limiting effect of an inductor is called ? and is symbolized by the letter ? . -
** VERIFIED ANSWERS **✔✔B. impedance/Z
Select the equation for determining the total impedance in an inductive and resistive circuit.
- ** VERIFIED ANSWERS **✔✔z= (square root Xl^2 +R^2)
A circuit has a resistance of 10 ohms and a voltage of 120 volts. How much current flows? -
** VERIFIED ANSWERS **✔✔12 A
I = E/R
= 120/10
=12A
, A circuit has an impedance of 5 ohms and a voltage of 100 volts. What is the current flow? -
** VERIFIED ANSWERS **✔✔20A
I = E/Z
= 100/5
= 20A
Which waveforms correctly show current and voltage to be "in-phase"? - ** VERIFIED
ANSWERS **✔✔b. Both have the same period and start point. but different amplitudes
In most AC circuits, the current and voltage are ? . - ** VERIFIED ANSWERS **✔✔out-of-
phase
These sine waves indicate voltage and current ? out-of-phase. - ** VERIFIED ANSWERS
**✔✔45°
There can be a phase difference between voltage and current in DC circuits. - ** VERIFIED
ANSWERS **✔✔False
The equation for finding power in a circuit when the current and voltage are known is ? . -
** VERIFIED ANSWERS **✔✔P = E x I
Drag the appropriate voltage and current sine wave and locate it to show the relationship of
voltage and current over a complete cycle for a purely inductive circuit. - ** VERIFIED
ANSWERS **✔✔Different amplitudes
In a pure resistive circuit, the true power (or watts) is equal to the product of the ? and ? . -
** VERIFIED ANSWERS **✔✔B. Current/Voltage
An electrical measurement called VARs is used to measure ? power. - ** VERIFIED
ANSWERS **✔✔Reactive