94.20: A magnet is dropped through a vegia ,) a5cq7lrg3 i (22x bfbq9gvn3znrtical copper pipe slightly larger than the magnet. Relative to the speed it would fall in air, the magnet in the pipe ) 59 a,fbnr3gvqq3ilcangb(722 i gxz falls:

  01.30: Lenz's law concerning the direction of an induced current in a conducto taz+w-7q+z1n xm f-ht(s cf/pr by a magnetic field could be a restatemwc7af1-z+ / -x tpzn+mft (qhsent of

  11.25: The product (3 Teslas) × (2 meters) × (4 metn5zgi56mi m (hxms y,1ers/second) is equivalent to whix56hmi imy15zngm(, sch one of the following?

  04.34: A square loop is placed in a uniform7q *st5g bbw ,p2iau;c magnetic field perpendicular to the plane of the loop as shown. The lw5 bp 7 iug,sqt2*ba;coop is 0.5 meters on a side and the magnetic field B has a strength of 2 T. If the loop is rotated through 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 through a magnetic field directed into the page. The wzi+ 77 ;kxcz6astd1 tlire experiences an induced charge separation as shown. Which wc6dskxz;7 tz1t+i 7laay is the wire moving?

  00.20: A wire moves with a velocityk0 ihb kc(jg-s5 y03sh v through a magnetic field and experiences an induced charge separation as shown. What is the direction of the magnetic field?5y (jh3s0b0 sckh ig-k

  05.33: The figure beloyhe-lql4g-f sf1c u .qknm ,l,i5* m+ow shows a bar moving to the right on two conducting rails. To make an induced current i in the direction indicated, in what direction would the magnetic field be in the arely* f+mlei., o,gck 4 5smqn ql-fu1h-a contained within the conducting rails?

  00.10: When a wire moving throkcu)17v mg ca z1:+;l vigcdkrh1 h*x*ugh a magnetic field has a voltage induced between the wire’s ends, that voltag7zamclvc 1kg1k *+cvgi hd1:;xh) *r ue is
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 copper rod has c . 7 r;mtwgwvqui6,fhq.f,70/bg vyn uonstant velocity 0.30 m/s traveling through a unifonr qhq 7;/mgwituwf,f60b,.7v .vyg urm 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 length?

  04.42: A solenoid is oriented end-on so that it.rev 0-lg/dee s opening is perpendicular to the circuit containing the two light bulbs as drawn in figure C1. For figures C2 and C3, a sv./ edrg-0el ehorting 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 uniformly 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 a unk4vy4 imvz(:x/ xcq9+k ;gzre assumed to be close to each other), the resistance of the left-hand circuit is slowly increased. In which direction does the galvanometer needle in the right-hand circuit move in response:k4vn4zi;v xq(/m x9k+ gu zyc to this change?

  08.29: A strong bar magnet is held very close to the opening of a solenoid 6c:qf2b oro ng/j6+gnj+7h idas shown in the diagram. As the magnet is moved away from the solenoid at constab/rj q ohg nci+goj6d+2n67:fnt speed, what is the direction of conventional current through the resistor shown and what is the direction of the force on the magnet because of the induced current?

  09.37: For the figure shown, thefay*zc6 :3 q e+rdlpe+ variable resistance in the circuit 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 the conventional current through ce:+*dy z l3ap +qef6rthe resistor in the right-hand circuit?

  10.39: A strong bar magnet ,5c-byfsuvyevj) ;y2is held very close to the opening of a solenoid as shown 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. yy ;eu, vvj-2cf b5y)sWhat is the direction of the force on 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 aib8:;per,l w7wj:)g3fjxs :h+l xtxn re placed next to each 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 conventio: 73 we8b;nxpjjw l:tf:ix x,hs+ rl)gnal current in the right-hand loop (as viewed in the figure from above)?

  11.41: For the figure shown, the variable resistance of the e )aaj2r 3 nmkp31n hkx71ybl6outer 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 variab)bk c z774im8-fjtl84 cxdk w ua7d*jile 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, conducting wire loop sits (sppa41k f.mof +xz7pin a plane perpendicular to a spatially uniform magnetic field pointing into the plane of the page as shown. The magnetic field strength steadilpz7s1aff +pp( .x k4omy increases with time. Which one of the following effects best describes the result of this field increase?

  16.47: Two small loops of wire are located close to a wire wr ws9i2i i-*rh;:azm hith conventional current directed up the page. A scientist then moves the loops away from the current as shown. What is the orientation of the conventional current in each loo;i:-9r rs *ii2 hwzhamp while this occurs?

  17.35: A metal bar is moving to the left across a set of friclb:u4 kc d--cth6 /oxotionless 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 shownt:4olcd /xh koc-bu -6?

  08.50:. An infinitely long solenoid passes through th 5r-;fjua vem9 asy7ulj29v76 fxigr 2e circuit as shown. The magnetic field of the solenoid, dir ;6i2uegr95af2am j7 fxv-9r 7uvyjs lected into the
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 py;bl2bc kd/ xt6jqte0k(f *r1 age is decreasing 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 ix6b 0(tdcjq lt;fk 1r*ky2be /n it and an ideal voltmeter connected to the corners through the center of the loop. What is the magnitude of the voltmeter’s reading?