What is the value of the hypotenuse of a right triangle whose sides are 12 and 18? 3.46 2.16 4.24 21.63 TRUE ANSWER : ? YOUR ANSWER : ?
What is the angular difference between +j4 and –j4? 180° 30° 270° 90° TRUE ANSWER : ? YOUR ANSWER : ?
A 47Ω resistor and a capacitor with a capacitive reactance of 120 are in series across an ac source. What is the circuit impedance, Z? 12.9Ω 167Ω 129Ω 73Ω TRUE ANSWER : ? YOUR ANSWER : ?
The voltages in Problem 4 are measured at a certain frequency. To make the capacitor voltage greater than the resistor voltage, the frequency is held constant must be increased must be decreased has no effect TRUE ANSWER : ? YOUR ANSWER : ?
When the frequency of the source voltage decreases, the impedance of a parallel RC circuit decreases to zero increases decreases does not change TRUE ANSWER : ? YOUR ANSWER : ?
A resistor and a capacitor are in series across a 20 V ac source. Circuit impedance is 4.33 k. Current flow in the circuit is 92 mA 4.6 mA 460 mA 9.2 mA TRUE ANSWER : ? YOUR ANSWER : ?
A 120Ω resistor is in parallel with a capacitor with a capacitive reactance of 40 Ω. Both components are across a 12 V ac source. What is the magnitude of the total impedance? 3.7Ω 37.9Ω 4800Ω 14400Ω TRUE ANSWER : ? YOUR ANSWER : ?
A positive angle of 30° is equivalent to a negative angle of –60° –330° –30° –180° TRUE ANSWER : ? YOUR ANSWER : ?
A 2 kΩ resistor and a 0.002 μF capacitor are in series across an ac source. Current in the circuit is 6.50 mA. The true power is 845 mW 130 mW 13 mW 84.5 mW TRUE ANSWER : ? YOUR ANSWER : ?
An ac circuit consists of a resistor and a capacitor. To increase the phase angle above 45°, the following condition must exist: R > XC R = XC R = 5XC R < XC TRUE ANSWER : ? YOUR ANSWER : ?