Two circular loops are side by side and lie in the xy-plane. A switch is closed, starting a counterclockwise current in the left-hand loop, as viewed from a point on the positive z-axis passing through the center of the loop. Which of the following statements is true of the right-hand loop?
1.The current remains zero.
2.An induced current moves counterclockwise.
3.An induced current moves clockwise.
[Ques. 2] A bar magnet is falling toward the center of a loop of wire, with the north pole oriented downward. Viewed from the same side of the loop as the magnet, as the north pole approaches the loop, what is the direction of the induced current?
1.clockwise
2.zero
3.counterclockwise
4.along the length of the magnet
[Ques. 3] The figure below is a graph of the magnitude B versus time for a magnetic field that passes through a fixed loop and is oriented perpendicular to the plane of the loop. Rank the magnitudes of the emf generated in the loop at the three instants indicated from largest to smallest.
1. c > b > a
2. a > b > c
3. b > c > a
4. b > a > c
[Ques. 4] If, in the figure below, I1 = 2 A and I2 = 6 A, which of the following is true?
[Ques. 5] Which of the following actions would double the magnitude of the magnetic force per unit length between two parallel current-carrying wires? Choose all correct answers.
(a) Double one of the currents.
(b) Double the distance between them.
(c) Reduce the distance between them by half.
(d) Double both currents.
1.(a) only
2.(a) and (c)
3.(b) and (d)
4.(c) and (d)
[Ques. 6] As a charged particle moves freely in a circular path in the presence of a constant magnetic field applied perpendicular to the particle's velocity, the particles kinetic energy
1.remains constant.
2.increases.
3.decreases.
[Ques. 7] A square and a circular loop with the same area lie in the xy-plane, where there is a uniform magnetic field pointing at some angle q with respect to the positive z-direction. Each loop carries the same current, in the same direction. Which magnetic torque is larger?
1.the torque on the square loop
2.the torque on the circular loop
3.the torques are the same
4.more information is needed
[Ques. 8] The north-pole end of a bar magnet is held near a stationary positively charged piece of plastic. The plastic is
1.attracted.
2.repelled.
3.unaffected by the magnet.
[Ques. 9] A charged particle moves in a straight line through a region of space. Which of the following answers must be true? (Assume any other fields are negligible.) The magnetic field<--EndFragment--> ack;mso-style-textfill-fill-alpha:100.0'> that is submerged in the water?
1.has a magnitude of zero.
2.has a zero component perpendicular to the particle's velocity.
3.has a zero component parallel to the particle's velocity.
[Ques. 10] The switch is closed in the figure below. After a long time compared with the time constant of the circuit, what will the current be in the 2-V resistor?
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