In: Physics
Choose the correct answer:
I)Two long parallel wires are placed side by side on a horizontal table. The wires carry equal currents in the same direction. Which of the following statements is true? A. The magnetic field is a maximum at a point midway between the two wires. B. The magnetic force between the two wires is repulsive. C. The magnetic forces between the two wires does not obey Newton's third law. D. The magnetic field at a point midway between the two wires is zero.
II)An inductor is connected across an AC source. Suppose the frequency of the source is doubled. What happens to the inductive reactance of the inductor? A. The inductive reactance is quadrupled. B. The inductive reactance is doubled. C. The inductive reactance remains constant. D. The inductive reactance is halved.
III) An ideal resistor, inductor, and capacitor are connected in series to an AC source. What is the phase angle between the voltages of the inductor and capacitor in this RLC circuit? A. The phase angle is 0°. B. The phase angle is 90°. C. The phase angle is 180°. D. The phase angle is 270°.