LEVEL 2 MODULE 1 ALTERNATING
CURRENTS CORRECTLY ANSWERED TEST
BANK 2026 UPDATED QUESTIONS WITH
ANSWERS GRADED A+
⩥ How does the direction of an alternating current change? Answer: The
direction varies every half cycle.
⩥ What shape describes the variation of current or p.d. with time in a.c.?
Answer: A sine curve (sinusoidal).
⩥ What type of motion do electrons in a wire carrying a.c. exhibit?
Answer: Simple harmonic motion.
⩥ What is the relationship between time period (T) and frequency (f) for
a.c.? Answer: They are inversely related; T = 1/f.
⩥ What is peak current (I0)? Answer: The maximum value of the
alternating current.
⩥ How can peak current or voltage be determined? Answer: From the
amplitude of a current-time or voltage-time graph.
, ⩥ What is peak-to-peak voltage? Answer: The distance between a
positive peak and the consecutive negative peak.
⩥ How is peak voltage (V0) calculated? Answer: V0 = peak-to-peak
voltage ÷ 2.
⩥ What are root-mean-square (rms) values used for? Answer: To
compare a.c. current or voltage to its equivalent direct current (d.c.).
⩥ What do rms values represent? Answer: The d.c. values that produce
the same heating effect as the a.c.
⩥ How is the rms value of an alternating current defined? Answer: The
square root of the mean of the squares of all the values of the current in
one cycle.
⩥ What is the formula for rms current (Irms)? Answer: Irms = 0.707 ×
I0.
⩥ What is the rms voltage (Vrms)? Answer: The square root of the mean
of the squares of all the values of the voltage in one cycle.
⩥ How is rms voltage related to peak voltage? Answer: Vrms = 0.707 ×
V0.
CURRENTS CORRECTLY ANSWERED TEST
BANK 2026 UPDATED QUESTIONS WITH
ANSWERS GRADED A+
⩥ How does the direction of an alternating current change? Answer: The
direction varies every half cycle.
⩥ What shape describes the variation of current or p.d. with time in a.c.?
Answer: A sine curve (sinusoidal).
⩥ What type of motion do electrons in a wire carrying a.c. exhibit?
Answer: Simple harmonic motion.
⩥ What is the relationship between time period (T) and frequency (f) for
a.c.? Answer: They are inversely related; T = 1/f.
⩥ What is peak current (I0)? Answer: The maximum value of the
alternating current.
⩥ How can peak current or voltage be determined? Answer: From the
amplitude of a current-time or voltage-time graph.
, ⩥ What is peak-to-peak voltage? Answer: The distance between a
positive peak and the consecutive negative peak.
⩥ How is peak voltage (V0) calculated? Answer: V0 = peak-to-peak
voltage ÷ 2.
⩥ What are root-mean-square (rms) values used for? Answer: To
compare a.c. current or voltage to its equivalent direct current (d.c.).
⩥ What do rms values represent? Answer: The d.c. values that produce
the same heating effect as the a.c.
⩥ How is the rms value of an alternating current defined? Answer: The
square root of the mean of the squares of all the values of the current in
one cycle.
⩥ What is the formula for rms current (Irms)? Answer: Irms = 0.707 ×
I0.
⩥ What is the rms voltage (Vrms)? Answer: The square root of the mean
of the squares of all the values of the voltage in one cycle.
⩥ How is rms voltage related to peak voltage? Answer: Vrms = 0.707 ×
V0.
