If two parallel, conducting plates have equal positive charge, the electric field lines will:
a. leave one plate and go straight to the other plate.
b. enter both plates from infinity.
c. leave both plates and go to infinity.
d. none of the above.
[Ques. 2] Tasha has mass 20 kg and wants to use a 6.0-m board of mass 10 kg as a seesaw. Her friends are busy, so Tasha seesaws by herself by putting the support at the system's center of gravity when she sits on one end of the board. How far is she from the support point?
a. 2.0 m
c. 0.67 m
b. 1.0 m
d. 0.33 m
[Ques. 3] A parallel-plate capacitor has a capacitance of 20 F. What potential difference across the plates is required to store 22 10-5 C on this capacitor?
a. 2.2 10-2 V
c. 11 V
b. 1.4 10-8 V
d. 70 V
[Ques. 4] A uniform bridge span weighs 70.0 103 N and is 40.0 m long. An automobile weighing 15.0 103 N is parked with its center of gravity located 12.0 m from the right pier. What upward support force does the right pier provide?
a. 24.5 103 N
c. 65.0 103 N
b. 35.5 103 N
d. 45.5 103 N
[Ques. 5] A 0.50-mF capacitor is connected to a 400 V battery. Find the charge on the capacitor.
a. 2.0 10-4 C
c. 1.0 10-4 C
b. 0.020 C
d. 1.2 10-12 C
[Ques. 6] A bucket of water with total mass 23 kg is attached to a rope, which in turn, is wound around a 0.080-m radius cylinder at the top of a well. A crank with a turning radius of 0.25 m is attached to the end of the cylinder. What minimum force directed perpendicular to the crank handle is required to just raise the bucket? (Assume the rope's mass is negligible, that the cylinder turns on frictionless bearings, and that g = 9.8 m/s2.)
a. 45 N
c. 72 N
b. 68 N
d. 135 N
[Ques. 7] Decreasing the voltage across the two plates of a capacitor will produce what effect on the capacitor?
a. decrease charge
c. decrease capacitance
b. increase capacitance
d. increase charge
[Ques. 8] A bucket filled with water has a mass of 23 kg and is attached to a rope, which in turn, is wound around a 0.080-m radius cylinder at the top of a well. What torque does the weight of water and bucket produce on the cylinder if the cylinder is not permitted to rotate? (g = 9.8 m/s2)
a. 34 Nm
c. 11 Nm
b. 18 Nm
d. 36 Nm
[Ques. 9] The unit of capacitance, the farad, is dimensionally equivalent to which of the following?
a. J/V
c. VC
b. C/V
d. V/C
[Ques. 10] Two children seat themselves on a seesaw. The one on the left has a weight of 400 N while the one on the right weighs 300 N. The fulcrum is at the midpoint of the seesaw. If the child on the right is not at the end but is 1.50 m from the fulcrum and the seesaw is balanced, what is the torque provided by the weight of the child on the left? (Take ccw as positive.)
a. 600 Nm
c. 600 Nm
b. 450 Nm
d. 450 Nm
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