AC 2B3 Practice Questions 2025 With
100% Correct Answers
The output waveform of a simple AC generator in one full revolution passes through zero volts:
A) 4 times
B) twice
C) once
D) 3 times
E) it does not pass through zero volts - CORRECT ANSWER✔✔twice
The voltage generated by a simple AC generator at any point of the armature's travel is
proportional to the size of the angle between the magnetic field and the direction of the motion
of the armature. This waveform is called:
A) a square wave
B) a sine wave
C) fluctuating DC
D) a cosine wave
E) a saw tooth wave - CORRECT ANSWER✔✔a sine wave
If the instantaneous output voltage of a sine wave generator is 240 volts at 45 degrees rotation
of the armature, what will be the peak output voltage?
A) 170 volts
B) 240 volts
,C) 339 volts
D) 480 volts
E) 678 volts - CORRECT ANSWER✔✔339 volts
What does a waveform show?
A) The shape of the wave
B) The voltages at any time
C) The frequency of the wave
D) The DC component of the wave - CORRECT ANSWER✔✔The shape of the wave
The number of cycles generated in one second is called:
A) a sine wave
B) the frequency
C) the wave length
D) a cycle
E) conductance - CORRECT ANSWER✔✔the frequency
One alteration of a sine wave takes 4 ms. What is the frequency of the wave?
A) 1 kHz
B) 250 Hz
C) 2.5 kHz
D) 400 Hz
E) 600 Hz - CORRECT ANSWER✔✔250 Hz
,An electric force of a DC circuit of 100 DC has 2 amperes flowing through it. What would be the
RMS value of an AC supply of 60HZ if the current flow was 4 amperes through the same electric
fire?
A) 200 V
B) 141.4 V
C) 282.8 V
D) 50 V
E) 400 V - CORRECT ANSWER✔✔200 V
The average value of a 60 Hz 200 RMS alternating sine over one cycle is:
A) 200 V
B) 314 V
C) 0 V
D) 180 V
E) 5 V - CORRECT ANSWER✔✔0 V
Every vector can be resolved into two that are 90 degrees apart. What is the magnitude of the
vector if the horizontal component is 5 volts and the vertical 12 volts?
A) 17 volts
B) 7 volts
C) 13 volts
D) 20 volts
E) 5 volts - CORRECT ANSWER✔✔13 Volts
, AC or rotating vectors of sine waves show:
A) the angle between phase
B) the amplitude of the wave
C) both the amplitudes and the phases relationships between the voltages and currents
D) the waveform of the wave
E) the cancellation factor - CORRECT ANSWER✔✔both the amplitudes and the phases
relationships between the voltages and currents
Which one of the statements is correct when a pure resistance load is on an AC circuit, the load
current is:
A) in phase with the voltage
B) leading the voltage by 90 degrees
C) lagging the voltage by 90 degrees
D) out of phase by 180 degrees
E) 45 degrees - CORRECT ANSWER✔✔in phase with the voltage
In a series DC circuit which of the following is true?
A) The voltage drop across the resistance is in phase with the current, while the voltage drop
across the capacitance lags the current by 90 degrees.
B) The voltage drop across the resistance and capacitance lags the current by 90 degrees.
C) The voltage drop across the resistance is in phase with the current, while the voltage drop
across the capacitance lags the current by 90 degrees.
D) the total voltage drop is inversely proportional to the total resistance
100% Correct Answers
The output waveform of a simple AC generator in one full revolution passes through zero volts:
A) 4 times
B) twice
C) once
D) 3 times
E) it does not pass through zero volts - CORRECT ANSWER✔✔twice
The voltage generated by a simple AC generator at any point of the armature's travel is
proportional to the size of the angle between the magnetic field and the direction of the motion
of the armature. This waveform is called:
A) a square wave
B) a sine wave
C) fluctuating DC
D) a cosine wave
E) a saw tooth wave - CORRECT ANSWER✔✔a sine wave
If the instantaneous output voltage of a sine wave generator is 240 volts at 45 degrees rotation
of the armature, what will be the peak output voltage?
A) 170 volts
B) 240 volts
,C) 339 volts
D) 480 volts
E) 678 volts - CORRECT ANSWER✔✔339 volts
What does a waveform show?
A) The shape of the wave
B) The voltages at any time
C) The frequency of the wave
D) The DC component of the wave - CORRECT ANSWER✔✔The shape of the wave
The number of cycles generated in one second is called:
A) a sine wave
B) the frequency
C) the wave length
D) a cycle
E) conductance - CORRECT ANSWER✔✔the frequency
One alteration of a sine wave takes 4 ms. What is the frequency of the wave?
A) 1 kHz
B) 250 Hz
C) 2.5 kHz
D) 400 Hz
E) 600 Hz - CORRECT ANSWER✔✔250 Hz
,An electric force of a DC circuit of 100 DC has 2 amperes flowing through it. What would be the
RMS value of an AC supply of 60HZ if the current flow was 4 amperes through the same electric
fire?
A) 200 V
B) 141.4 V
C) 282.8 V
D) 50 V
E) 400 V - CORRECT ANSWER✔✔200 V
The average value of a 60 Hz 200 RMS alternating sine over one cycle is:
A) 200 V
B) 314 V
C) 0 V
D) 180 V
E) 5 V - CORRECT ANSWER✔✔0 V
Every vector can be resolved into two that are 90 degrees apart. What is the magnitude of the
vector if the horizontal component is 5 volts and the vertical 12 volts?
A) 17 volts
B) 7 volts
C) 13 volts
D) 20 volts
E) 5 volts - CORRECT ANSWER✔✔13 Volts
, AC or rotating vectors of sine waves show:
A) the angle between phase
B) the amplitude of the wave
C) both the amplitudes and the phases relationships between the voltages and currents
D) the waveform of the wave
E) the cancellation factor - CORRECT ANSWER✔✔both the amplitudes and the phases
relationships between the voltages and currents
Which one of the statements is correct when a pure resistance load is on an AC circuit, the load
current is:
A) in phase with the voltage
B) leading the voltage by 90 degrees
C) lagging the voltage by 90 degrees
D) out of phase by 180 degrees
E) 45 degrees - CORRECT ANSWER✔✔in phase with the voltage
In a series DC circuit which of the following is true?
A) The voltage drop across the resistance is in phase with the current, while the voltage drop
across the capacitance lags the current by 90 degrees.
B) The voltage drop across the resistance and capacitance lags the current by 90 degrees.
C) The voltage drop across the resistance is in phase with the current, while the voltage drop
across the capacitance lags the current by 90 degrees.
D) the total voltage drop is inversely proportional to the total resistance
