Level 2 Module 1 Alternating Currents
The hertz rating of an AC circuit is ? If the frequency is 20 cycles per 1/2 seconds ? -
ANSWER 40
F= c/t
A circuit has a RMS voltage of 120vac, the peak voltage is? - ANSWER 170
Rms=.707 x peak
The step down turns ratio of a transformer with 200 Turns in the primary and 100
turns in the secondary is ? - ANSWER 2:1
Opening the secondary of a CT under load will cause a dangerous level of ? -
ANSWER Induce high voltage
A circuit has a peak voltage of 275 volts, the average voltage is ? - ANSWER 175
Average = .637 x peak
Three equal capacitors in series has _____ of the applied voltage ? - ANSWER
1/3V
The formula for inductive reactance is ? - ANSWER Xl = 2pieFL
The current in an inductive circuit ______ the voltage ? - ANSWER Lags
The current in an AC circuit with resistance only is ? The circuit has a resistance of
15 ohms and a voltage of 150 volts? - ANSWER 10
I = e/r
Capacitive reactance ______ when the frequency increase ? - ANSWER Decrease
The current in a capacitive circuit ____ the voltage ? - ANSWER Leads
The average value of an AC sine wave is ____ Times the peak value ? -
ANSWER .637
All DC rules and laws including ohm's law apply in AC circuits containing only ? -
ANSWER Pure resistance
To increase the capacitance of a capacitor _____ the area of the plates ? -
ANSWER Increase
The self induced voltage across an inductance is equal to the change in ______ with
the respect to time ? - ANSWER Current
What is the total capacitance of a 30 microfarad capacitor in parallel with a 15
microfarad capacitor ? - ANSWER 45
The hertz rating of an AC circuit is ? If the frequency is 20 cycles per 1/2 seconds ? -
ANSWER 40
F= c/t
A circuit has a RMS voltage of 120vac, the peak voltage is? - ANSWER 170
Rms=.707 x peak
The step down turns ratio of a transformer with 200 Turns in the primary and 100
turns in the secondary is ? - ANSWER 2:1
Opening the secondary of a CT under load will cause a dangerous level of ? -
ANSWER Induce high voltage
A circuit has a peak voltage of 275 volts, the average voltage is ? - ANSWER 175
Average = .637 x peak
Three equal capacitors in series has _____ of the applied voltage ? - ANSWER
1/3V
The formula for inductive reactance is ? - ANSWER Xl = 2pieFL
The current in an inductive circuit ______ the voltage ? - ANSWER Lags
The current in an AC circuit with resistance only is ? The circuit has a resistance of
15 ohms and a voltage of 150 volts? - ANSWER 10
I = e/r
Capacitive reactance ______ when the frequency increase ? - ANSWER Decrease
The current in a capacitive circuit ____ the voltage ? - ANSWER Leads
The average value of an AC sine wave is ____ Times the peak value ? -
ANSWER .637
All DC rules and laws including ohm's law apply in AC circuits containing only ? -
ANSWER Pure resistance
To increase the capacitance of a capacitor _____ the area of the plates ? -
ANSWER Increase
The self induced voltage across an inductance is equal to the change in ______ with
the respect to time ? - ANSWER Current
What is the total capacitance of a 30 microfarad capacitor in parallel with a 15
microfarad capacitor ? - ANSWER 45
