G5A – Reactance; inductance; capacitance; impedance; impedance transformation; resonance - [[G5A01]] (C) What happens when inductive and capacitive reactance are equal in a series LC circuit? #card - A. Resonance causes impedance to be very high - B. Impedance is equal to the geometric mean of the inductance and capacitance - C. Resonance causes impedance to be very low - D. Impedance is equal to the arithmetic mean of the inductance and capacitance - [[G5A02]] (B) What is reactance? #card - A. Opposition to the flow of direct current caused by resistance - B. Opposition to the flow of alternating current caused by capacitance or inductance - C. Reinforcement of the flow of direct current caused by resistance - D. Reinforcement of the flow of alternating current caused by capacitance or inductance - [[G5A03]] (D) Which of the following is opposition to the flow of alternating current in an inductor? #card - A. Conductance - B. Reluctance - C. Admittance - D. Reactance - [[G5A04]] (C) Which of the following is opposition to the flow of alternating current in a capacitor? #card - A. Conductance - B. Reluctance - C. Reactance - D. Admittance - [[G5A05]] (D) How does an inductor react to AC? #card - A. As the frequency of the applied AC increases, the reactance decreases - B. As the amplitude of the applied AC increases, the reactance increases - C. As the amplitude of the applied AC increases, the reactance decreases - D. As the frequency of the applied AC increases, the reactance increases - [[G5A06]] (A) How does a capacitor react to AC? #card - A. As the frequency of the applied AC increases, the reactance decreases - B. As the frequency of the applied AC increases, the reactance increases - C. As the amplitude of the applied AC increases, the reactance increases - D. As the amplitude of the applied AC increases, the reactance decreases - [[G5A07]] (D) What is the term for the inverse of impedance? #card - A. Conductance - B. Susceptance - C. Reluctance - D. Admittance - [[G5A08]] (C) What is impedance? #card - A. The ratio of current to voltage - B. The product of current and voltage - C. The ratio of voltage to current - D. The product of current and reactance - [[G5A09]] (B) What unit is used to measure reactance? #card - A. Farad - B. Ohm - C. Ampere - D. Siemens - [[G5A10]] (D) Which of the following devices can be used for impedance matching at radio frequencies? #card - A. A transformer - B. A Pi-network - C. A length of transmission line - D. All these choices are correct - [[G5A11]] (B) What letter is used to represent reactance? #card - A. Z - B. X - C. B - D. Y - [[G5A12]] (D) What occurs in an LC circuit at resonance? - A. Current and voltage are equal - B. Resistance is cancelled - C. The circuit radiates all its energy in the form of radio waves - D. Inductive reactance and capacitive reactance cancel