94.20: A magnet is dropped through a vertical copper pipe slightly largexusgmpe e 61/5r than the magnet. Relative to the sueg1 / mp5xs6epeed it would fall in air, the magnet in the pipe falls:

  01.30: Lenz's law concerning the direction of an induced current in a cts+0cdn;9-fr hh ph n9onductor by a magnetic field could be ar-t n9cd+09hs nhp;fh restatement of

  11.25: The product (3 Teslas) × (2 meters) × (4 m-z- e5+ oy sore)hatg*eters/second) is equivalent to which one of the following?5 eogh z-y*eota-)+s r

  04.34: A square loop is placed in a uniform magnetic field perpendico6rv99vta z( weobu f/+ fw1sgy/03ctular to the plane of the loop as shown. The loop is 0.5 meters on a side and the magnetic field B has a strength of 2 T. If the loop is rotated througe9t1 rwafz g/oy6ocbv ws0 (t9+vf3u/ h an angle of $90^{\circ}$ in 0.1 second what would be the average (RMS) induced EMF in the loop?

  97.32: A wire moves t1,4um t 6wfwzo8rnx*qhrough a magnetic field directed into the page. The wire experiences an induced charge separation as shown. Which way is the w1x*,w zf8 ton quw4r6mire moving?

  00.20: A wire moves with a velocity v through a magnexum;y 7tlupa5vl s; 0ztt1u26 tic field and experiences an induced charge separation as7l1zt2p6stuuy t xmv0u; a; 5l shown. What is the direction of the magnetic field?

  05.33: The figure below jgrdhx9a+ 38kshows a bar moving to the right on two conducting rails. To make an induced current i ingj3 hkd8arx9+ the direction indicated, in what direction would the magnetic field be in the area contained within the conducting rails?

  00.10: When a wire moving(.tnxeizug9p dhr w((7cp 2p- through a magnetic field has a voltage induced between the wire’s ends, that voltage idc 9ptx(zph(pnrg e7w(- .i2 us
I. directly proportional to the strength of the magnetic field
II. directly proportional to the velocity of the wire
III. directly proportional to the diameter of the wire

  95.30: A 0.20 m long copperu nx5alga.c)gxk 1+l3 rod has constant velocity 0.30 m/s traveling through a uniform magnetic field of 0.060 T. The rod, velocity, and magnetic field are all mutually perpendicular. What is the potential difference induced across the rod’s len uk.5lxa1+x3ng)cgalgth?

  04.42: A solenoid is oriented enmag, na;h,tj 3d-on so that its opening is perpendicular to the circuit containing the two light bulbs as drawn in figure C1. For figures C2 and C3, a shorting wire of negligible resistance is added as shown. Assume that the magnetic field from the solenoid, shown coming out of the plane of the page, decreases unnmgjt3a, ;,haiformly in time at the same rate for each circuit. Rank the circuits for the brightness of the bulb labeled R1 from brightest to dimmest.

  07.34 For the solenoids shown in the diagram (which are assumed to be clog2v ba7x ektg. 4dl.,bse to each other), the resistance of the left-hand circuit is slowly increased. In which direction does the galvanometer ,bd2b4ga.7.tlgxek v needle in the right-hand circuit move in response to this change?

  08.29: A strong bar magnet is held very close to the opening of a sole .1dvt5xq(dgexdxp)ls 85z(enoid as shown in the diagram. As the magnet is moved away from the solenoid at constant speed, what is the direction of conventional current through the resxq t5)5dx(8pe1 evs dgld(.zxistor shown and what is the direction of the force on the magnet because of the induced current?

  09.37: For the figure shown, the variable resistance in the circue .2w9wwjkc g.it on the left is increased at a constant rate. What is the direction of the magnetic field at the point P at the center of the left-hand circuit and in what direction is .we2 kwwjg c9.the conventional current through the resistor in the right-hand circuit?

  10.39: A strong bar magnet is held very close to the opening of a solenoid as (o2 e)vkdnpx x0. x)ffshown in the diagram. As the magnet is moved to the left toward the solenoid, a conventional current through the resistor shown is directed from A to B. What is the direction of the force onnv0po)ekxd2.)x ( fxf the bar magnet because of the induced current in the solenoid and which magnetic pole does the “??” in the diagram represent?

  14.34: Two circular loops of resistive wire are placed next to ntmhk2vonm 1- +,teq2 *hzz1ceach other as in the figure. The circular loop on the left is connected to a constant voltage source V. The resistance of this loop is increasing linearly with time. As the resistance is changing, what is the direction of the magnetic field at point P (the center of the left-hand loop) and what is the orientation of the conventional current in the rightttnhem mkh2o n- 1vcz,+qz2* 1-hand loop (as viewed in the figure from above)?

  11.41: For the figure shown, the variable resistance of thcl. ldsrf0 faj)jfh2wj 0v290 e outer circuit $R_{inner}$ is decreasing at a constant rate. While this is occurring, in which direction is the magnetic field associated with the outer circuit at the point P in the plane of the circuit and in which direction is the conventional current through the resistor $R_{outer}$ in the smaller interior circuit? The two circuits lie on a flat table.

  13.35: For the figure shown, the variab5fx8so c5nw b3le resistance of the innercircuit $R_{inner}$ is increasing at a constant rate. While this isoccurring, in which direction is the magnetic field associated with the inner circuit at the point P in the plane of the circuitand in which direction is the flow of electrons through the resistor labeled $R_{outer}$?

  12.38: A square, conducphkibbs+ yc4sr;0v*; r(mkb6 ting wire loop sits in a plane perpendicular to a spatially uniform magnetic field pointing into the plane of the page as shown. The magnetic field strength steadily increases with time. Which one of the following effects best describes the result of this field increav;4ky+ 6 cs 0(mpris r;bkbhb*se?

  16.47: Two small loops of wire are locate3tp :1ntn /lvpp 48gtsqc7 j/gd close to a wire with conventional current directed up the page. A sci7l n/t pstjg8 n4:pgcqv/pt31entist then moves the loops away from the current as shown. What is the orientation of the conventional current in each loop while this occurs?

  17.35: A metal bar iwx*7np be/(zns moving to the left across a set of frictionless conducting rails as seen in the figure. Throughout the region between the rails, there is a uniform magnetic field directed into the plane of the page. The resistors labeled X and Y are identical. Which one of the following choices correctly indicates the direction of the conventional current in the resistors and the relation between the magnitude of the currents through each resistor at the instant shnzewb nxp*/ 7(own?

  08.50:. An infinitely long solenoid passes through the co ,/ lb, v3 qfibq9vnu,yenbtgc6 9 /7xg2sc4iircuit as shown. The magnetic field of the solenoid, directed into theengt2sx,b9 c gq co9y4 7l,6 v3/uf/qbbin ,iv
plane of the page, is weakening which produces a constant emf of magnitude ξ for a closed loop around the outside of the solenoid. Once equilibrium is established in this circuit, what is the voltage across the switch S?

  15.50 A magnetic field directed into the plane of the page is czs3;5ybko +65kldlp3e5 2bet om1 oqdecreasing in time. A constant emf ξ is produced for the square loop enclosing the field in the figure. The square loop has three identical light bulbs of resistance R in it andl2olk1 5ze3ysbt m3 ;+pooe6dbq55kc an ideal voltmeter connected to the corners through the center of the loop. What is the magnitude of the voltmeter’s reading?