Two point charges each have a value of 35.5 mC and are separated by a distance of 4.0 cm. What is the electric field midway between the two charges? (ke = 8.99 109 Nm2/C2)
a. 7.1E+8 N/C
b. 3.5E+8 N/C
c. 1.8E+8 N/C
d. zero
e. 2.0E+8 N/C
[Ques. 2] Resonance occurs in an AC series circuit when which of the following conditions is met?
a. resistance equals capacitive reactance
b. resistance equals inductive reactance
c. capacitive reactance equals inductive reactance
d. capacitive reactance equals zero
[Ques. 3] Five equal negative charges are uniformly spaced in a semicircular arc of radius r0 with its center at the origin. The charges positions in polar coordinates are given by (r0, i), where the values of i are 0, 45, 90, 135, and 180. At the position (x, y) = (r0, r0) in the 4th quadrant, which statement best describes the direction of the resulting electric field?
a. The direction is that of a 4th quadrant angle.
b. The direction is that of a 3rd quadrant angle.
c. The direction is that of a 1st quadrant angle.
d. The direction is that of a 2nd quadrant angle.
[Ques. 4] An RLC circuit is connected across an AC power source. Which statement is correct?
a. The voltage across the inductor lags the current by 90.
b. The voltage across the capacitor is in phase with the current.
c. At resonance, the phase angle / between the current and the voltage is 0
d. None of the above statements are correct.
[Ques. 5] The electric field of a point charge has an inverse ________ behavior.
a. r1/2
b. r
c. r2
d. r3
[Ques. 6] An LCR circuit has resistance R0, inductance L0, and capacitance C0 . If the resistance value is now tripled, which values of inductance and capacitance will result in the same resonant frequency as before?
a. 3L0, C0 b. L0/3, C0/3
c. 3L0, 3C0 d. 3L0, C0/3
[Ques. 7] Electric field is dimensionally equivalent to which of the following?
a. N/m/C
b. N/C
c. N/m2/C2
d. N/C2
[Ques. 8] At what frequency does a 0.32-H inductor have the same reactance as a 0.22-F capacitor?
a. 3.8 103 Hz b. 3.6 105 Hz
c. 24 Hz d. 6.0 102 Hz
[Ques. 9] A charged particle with mass m is suspended in the air by an upward-directed electric field E. What is the charge on the dust particle?
a. q = mgE
b. q = mg/E
c. q = E/mg
d. q = Em/g
[Ques. 10] When an RLC series circuit is in resonance, its impedance is:
a. zero.
b. equal to its resistance.
c. a maximum.
d. /2 .
Quick Reply
