94.20: A magnet is dropped through a vertzydnj+r/4zbitt+ m2 n c+0nv) ical copper pipe slightly larger than the magnet. Relative to the speed it would fall in air, the magnet in the pipe fd zv m tcn2jt+r+z0y+nnib)4/alls:

  01.30: Lenz's law concerning thpn)/ x 1 )eztr1afqz+ve direction of an induced current in a conductor by a magnetic field co)1a1fxz tn/zq e)+rpvuld be a restatement of

  11.25: The product (3 Teslas) × (2 meters) × (4 meters/second) is equivalent n 4rtt+6 bvr:e4mhtf )mwo1+ m.mn( lqto whicre+m:q(b.n 46mh w4t1 t rn fvmo)mlt+h one of the following?

  04.34: A square loop is placed in a uniform magnetic field perpendiceep+du01xaz.4 2c* cw(cuk skular to the plane of the loop as shown. u*ck4(ewx+2 ks cz.1pceda0 uThe loop 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 dh4m* :ivp4z.cji cgv4 irected into the page. The wire experiences an induced charge separation as shown. Which way is the wire movigcv c 4z*:mp.v4jhii4ng?

  00.20: A wire moves with a velocity v through a magnetizz2b8ujvv7i.78kg l oq7 pfto:gc:g,c field and experiences an inducedpgvlcz:,b8ofgzu7k2 t8q voj:ig 7. 7 charge separation as shown. What is the direction of the magnetic field?

  05.33: The figure below shore603 ffunv. /aw-6yc84/dbsij cqi nws 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 area containnbwdc/s0ic/fyerv 6a4-68q .ijuf3 ned within the conducting rails?

  00.10: When a wire moving through a magnetic field has 9ks- 2*ezcmyptm;c0 d a voltage induced between the wire’s ends, that-;tsp2c* d 0 9mzyemkc voltage 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 constant velocity (6y8 utx 3gute0.30 m/s traveling through a uniform magnetic field ofteg( 3xu8t6u y 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 its opef9j:n b f5l 31brscn e./tt(mmning is perpendicular to the circuit containing the two light bulbs as drawn in3m 1me9lbrt5nc.fs (f /nj:bt 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 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/-h(dd kc sqrgv0 1wq* are 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 to this svwhdd1 -(g/qkcr*q0 change?

  08.29: A strong bar magnet is held very close to the opening of a solenoan8e0bjm 05g aid 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 am80j5na 0bge 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 circuit on the ntka105mk+s o 3dfz ,+ ee9croleft 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 ds59 03ocafke 1+zn+tek,rmo what direction is the conventional current through the resistor in the right-hand circuit?

  10.39: A strong bar magnet is hey6:vj( qqtk8 tld 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 resis 8y (6tqvt:qjktor 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 represent?

  14.34: Two circular loops of resistiv:i oongb3kw+c vi /) (/t lp/c4hoxa:we wire are 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 directiwh avockico3/ : /pw+g(l/) o4x :nbiton 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 viewed in the figure from above)?

  11.41: For the figure shown, the va+jf +gfrd/z5 w rxx13+muwne/riable resistance of the 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 variable resistance of the innercircuk)*fcv lp vs7)e.i7 2bu (ymbkit $R_{inner}$ 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 sit ,r8d6ij ktwi,s in a plane perpendicular to a spatially uniktwj,,6drii 8 form 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 increase?

  16.47: Two small loopsby3w1ztcstm a)r1 8(i of wire are located close to a wire with conventional current directed up the page. A scientist then moves the loops away from the cur cr sw1iz1) 3tat8myb(rent as shown. What is the orientation of the conventional current in each loop while this occurs?

  17.35: A metal bar is moving to the left across a set o ekjl1.- o;b*id8rmdff 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 idenj de1ob8l*i k.dr- f;mtical. 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 circuit as show9kltlqa0ylf p(rm0u 0si*.j/ n. The magnetic field of the solenoid, d9*a fk0y i0lsj (rtlp0m/.uqlirected 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 d3z .w ekq)*4:kxayjndirected 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 iden*k):. 3z a4weykxdjqntical 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 voltmeter’s reading?