Module 4 Alternating Circuit Currents
- An AC circuit has a load current of 5A, and an effective voltage of 208V. The phrase angle is 30 degrees. Calculate the apparent power
- Determine the average voltage of the waveform shown in Figure 4-9
- Average value of a non sinusoidal wave over one cycle is called the
Pulse width
Pulse term
Duty cycle
Pulse amplitude
Phase difference
- When 60 Hz is supplied to a lamp, the map turns on and off ____ times per second
30
60
90
120
240
- A ratio of the conducting time to the period of one cycle is called the:
Pulse width
Pulse term
Duty cycle
Pulse amplitude
Phase difference
- The most common AC waveform is the ___ wave.
- The total change flowing for one complete cycle divided by the time taken to complete the cyle is the
Average
Mean
Peak to peak
Amplitude
Argument
- A transformer that is designed to provide two separate secondary voltages with a common connection is called a _____ transformer
- In a purely reactive circuit, the voltage and current are ____ out of phase with each other
30
45
80
90
120
- The secondary winding of an isolation transformer is said to be ____ because it is no longer referenced to the ground on the primary side
11 In AC circuits, the current and voltage are represented by ___ and ____
- The two windings on a transformer are called the ____ and _____
- When the AC transmission voltage is doubled , the weight of conductor:
Increases by 50%
Increases by 25%
Decreases by 25%
Decreases by 50%
Stays the same
- Inductors and capacitors react to the changing AC signal and produce an opposition to current flow called
15.
A predominantly capacitive circuit will have a phase displacement where the current ____ the voltage
- When voltage and current pass through their zero values and increase to their maximum values at the same time and in the same direction, the two waves are said to be ____ with each other
- In electronic circuits, rise time is defined as the amount of time required for the signal to rise to ___ % of its maximum amplitude
- To find the corresponding value of power between resistive and reactive circuits, the product of voltage and current is:
Divided by the sine of the phase angle
Multiplied by the cosine of the phase angle
Divided by the cosine of the phase angle
Multiplied by the sine of the phase angle
Multiplied by the square root of the phase angle
- Transformer windings are often built up in the flat sections called ____ coils
20 In an electronic circuit, the maximum value of voltage or current on the vertical axis is called the
RMS
Amplitude
Argument
Peak to peak
Average
- The amplitude of a waveform from its positive peak to its negative peak value is called the ___ value
Average
Peak to peak
RMS
Instantaneous
Peak
22.
For the waveform shown in Figure 4-8 calculate the period
- The time between the start of the rise and start of the all of the input pulse is called the
Pulse width
Pulse term
Duty cycle
Pulse amplitude
Phase difference
- In figure 4-5 the dots represent:
Terminals with the same instantaneous polarity
H1 an H2 terminal markings
X1 and X2 terminal markings
American Standards Association markings
Step up and step down configuration
- The DC equivalent of the AC power supplied by the source is called the
True power
Real power
Actual power
Apparent power
Average power
- The ratio of the direct current of equal power relative to the given alternating current is called the ___ factor
- The schematic symbol shown in Figure 4-3 is for a ___ transformer
Iron core
Step up
Center tap
Ferrite core
Air core
- IN an AC circuit, the product of the voltage and current is called the
True power
Real power
Actual power
Apparent power
Average power
29 Battery management system in EVs typically transmit control system information at a frequency of
2 KHz
200 kHz
2 MHz
20 MHz
2 GHz
- Unless otherwise specified, an alternating current or voltage is always stated as a ___ value
Average
Peak
Peak to peak
RMS
Instantaneous
