WorksheetsUnderstanding AC Current Concepts
Total questions: 10
Worksheet time: 5mins
In an AC circuit, what is the term used to describe the opposition to the flow of alternating current due to inductance and capacitance?
Resistance
Reactance
Impedance
Conductance
What is the formula for calculating the average power in an AC circuit?
P=VI
P=I2R
P=VIcosϕ
P=V2/R
In an AC circuit, if the voltage leads the current by 90 degrees, what type of component is likely present?
Resistor
Inductor
Capacitor
Transformer
What is the peak voltage of an AC supply if the RMS voltage is 230V?
230V
325V
115V
460V
Which device is used to change the voltage level in an AC system?
Rectifier
Transformer
Transistor
Diode
What is the frequency of the standard AC supply in Great Britain?
50 Hz
60 Hz
100 Hz
120 Hz
If the frequency of an AC wave is 50 Hz, what is its wavelength in metres, assuming the speed of light is 3×108 m/s?
6000 m
3000 m
1500 m
750 m
In an AC circuit, what is the phase difference between voltage and current in a purely capacitive circuit?
0 degrees
45 degrees
90 degrees
180 degrees
What is the unit of reactive power in an AC circuit?
Watt
Volt-Ampere
Volt-Ampere Reactive
Joule
Which of the following is true for a transformer in an AC system?
It can increase or decrease DC voltage.
It can only increase AC voltage.
It can only decrease AC voltage.
It can increase or decrease AC voltage.
