94.20: A magnet is dg6w-9(6 q-sjf yjjnn lropped through a vertical copper pipe slightly larger than the magnet. Relative to the speed it would fall in air, the magnet in the pipe falls:wj(nj g -lj6 qfnsy-69

  01.30: Lenz's law concerning the direction of an induced current in a( 1/tee*x we0;i mgeda conductor by a magnetic field could be a restateme m0/ xgaeeet*;d(ie1 wnt of

  11.25: The product (3 Teslas) × (2 meters) × (4 meters/-ybryt x6+ sp,second) is equivalent to which one ofx ,r 6ys+p-tby the following?

  04.34: A square loop is placed in ab.m .b;vf) ezf uniform magnetic field perpendicular to the plane of the loop as shown. The lfef.bz;) bmv.oop 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 dipkvu;+ncf0j5+ h8y 0q7:pnwgv:ay crrected into the page. The wire experiences an induced charge separation as shown. Which way is the wire movinnrcug 07 k :py vn8vf:+qy+ac5hw ;j0pg?

  00.20: A wire moves with a velocity v through a magnetic fjc e-g 4-t2dnqh (s+woield and experiences an induced charge separation as shoh t--2j edo(w4qsnc g+wn. What is the direction of the magnetic field?

  05.33: The figure below shows a bar moving to the right on two conducting railug)85 whj(b8b3cjdbhtd : h 5kl ) .bpqu;q-ljs. To make an induced current i in the direction indicated, in what direction would the magnetic field be in the area containw8 hjh-d8ulbj5;) lqbk5cb ) (gd:u.phb 3tjqed within the conducting rails?

  00.10: When a wire moving through a ma gw3n(5 mun+ /gp1ckhdgnetic field has a voltage induced between the wire’s ends, that voltage i/d3wun hc mkn( g1p+g5s
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 constant velocity 0.30 mfhlu w., ccqa9mp*:j we5b:i +/s traveling through a uniform magnetic field of 0.060 T. The rod, velocf+el:w,u9wqj i:cahb5* pcm. ity, and magnetic field are all mutually perpendicular. What is the potential difference induced across the rod’s length?

  04.42: A solenoid isah9jmgv2+g j upu8t. 0 oriented end-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 outm9ph vu.gug0jt82j+ a 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 dpozofg/(ev4j,r (:or iagram (which are assumed to be close to each other), the resistance of the left-hand circuit is slowly increased. In which direction does the galvanometer needl: ,vjoz e(p /goo4rr(fe in the right-hand circuit move in response to this change?

  08.29: A strong bar mx sd).hlzrfzdylsa*7*p;1 *cagnet is held very close to the opening of a solenoid 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 resistor shown and what is the direction of the force on the magnet because of the induced curzyc*hds * 7p;l)fzaxs l.d* r1rent?

  09.37: For the figure shown, the variable resistance in the /tp(v)p 78iuy 1moq oocircuit on the left is increased at a constant rate. ) (upom7/qoy1 pv8tio 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 the resistor in the right-hand circuit?

  10.39: A strong bar magnet is held very close to the opening glo6ymd)9 628kk u5os(jzm-shs z-rpof 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. What 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 represen2m(dks pyooz lu g-m)zss5-j9h 6 6rk8t?

  14.34: Two circular loops of resistive wire are placed next to zca01kgl. 9gld su5;reach 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 right-hand loop (as viewer g9 1azd;s0kl.u g5lcd in the figure from above)?

  11.41: For the figure shown, the variable resistance of the ou py7,3fjya*gouv* 7; rospsti582sme ter 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 vari bksb1q*y16q 0stw1fpc,ztun l)6tzy; 5s,yl able 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 in a plane perpendicular to a ;/nh o;di6hb0 sptq 3b*rc;aq- j;lnjspatially uniform magnetic field pointing into the plane of the page as shown. The magnetic fielabidqsrh03; /pbl tnq 6*;;jhj -co n;d strength steadily 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 with conven/) s- xjxiw,s uo4h4lvtional 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 loop while this occurs?-o xx4wjvl4i s) h,su/

  17.35: A metal bar is moving to the left across a set of fr(om :v6 / +dgnkejdf)uo,4emgictionless conducting rails as seen in the figure. Throughout the ro+gu 6fv(m) km:jdone de/4g,egion 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 shown?

  08.50:. An infinitely long solenoid passes through the cigi*n,z)dozxl,uis/ e0px2 i * rcuit as shown. The magnetic field of the solenoid, directed intos *l,d)zgi2e/u0 ,o*zxx nipi 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 dirb3v i(,akc0 m*crst 4nected into the plane of the page 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 in it and an ideal voltmeter connected to the corners through the center of the loop. What is the magnitude of the voakr *4s,v3c b0nc( imtltmeter’s reading?