94.20: A magnet is dropped through a vertical xb-d jexv :w)c0hs,f 0copper pipe slightly larger than the magnet. Relative to the speed it would fall in air, the magnet in the xde) jv0f:b0 hw-,cxs pipe falls:

  01.30: Lenz's law concerning the direction, ze .xb9gct/h; uso78:caerh of an induced current in a conductor by e:h,;eosrx 87g/. zc 9c atuhba magnetic field could be a restatement of

  11.25: The product (3 Teslas) × (2 meters) × (4h5ix h4alve* u abrbdly *-k.a3) :g0n meters/second) is equivalent to which one of thi n lalx vkdb)g*h4: 3er.h5b0a -y*uae following?

  04.34: A square loop is placed in a unifoi,won+8xvhs gcpw6+o, zd5 - zrm magnetic field perpendicular to the plane of the loop as shown. The loop is 0.5 meters on a side and the mahzzi,v-5n+w,86g csx+oo p wd gnetic 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 fieili2 m7 zj0w9xld directed into the page. The wire experience0wmjz2x 9li7 is an induced charge separation as shown. Which way is the wire moving?

  00.20: A wire moves with a velocity v through a magnetic field and experien:c6jss8r;rv 3l /gpv0k6 7yg bpnv.3v, rkf omces an induced charge separation as shown. What is the direction of thyrb3/skv 6rvmpf ;lvokrsg0 . c6v7 8j3,gpn:e magnetic field?

  05.33: The figure below shows a bar moving to the riqm ))zh(r/-wl zf1nz ight 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 contai iq fm )-)h(znlwrzz1/ned within the conducting rails?

  00.10: When a wire moving through a magnetic field has o 1/9q l rmf2qvry:tf0a voltage induced between the wire’s ends, that voltage ifqlf q oy r:/10vrtm92s
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 dxyea0wxg 0gt3(4-vamo2ho6has constant velocity 0.30 m/s traveling through a d0oo6x yg-4x ev2 at g3mahw0(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 length?

  04.42: A solenoid is oriented end-on so that its opening i ovvhe x3x)capv;.i5: s perpendicular to the circuit containing the two light bulbs as drawn in figure C1. For figure 5 hcv).px e;xiva:ov3s 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 ineq3xle6 k-c /c the diagram (which are assumed to be close to each other), the resistance of-cc36 ex klqe/ the left-hand circuit is slowly increased. In which direction does the galvanometer needle in the right-hand circuit move in response to this change?

  08.29: A strong bar magnet is held very cloja/373c0tn. mchh n w5ftp)g.x:i 6ym4 aya hyse 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 0m/ywyp h7 35ticy:aa3h)j 6nt4 fhn.cgmx.athe resistor 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 resistanyctm;y;yc9q- +6i2ssyse - kkce in the circuit on the left is increased at a constant rate. What is the directici+ymyt; sy; k-qkce- ssy962on 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 of a solenoid as 0ym9 +o7p cmh ks4nq-zshown in the diagram. As the magnet is moved to the left toward the solenoid, a conventional current through the re9 4hycns-mq0op+ km 7zsistor 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 reo+da4 8o74m )hzw hmc9o1 rft b3xzmc9: lca1tsistive 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 loopmo4+34btl zhwhcmaxdfct1)1o8 omr:c z7a99 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 viewed in the figure from above)?

  11.41: For the figure shown, the variable resistan1a ocrn:ha97 zv7bha cc .p+p0ce 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 s bulq1wm(.sala(37e 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 r e;f9)j(gn7 6lqxmvyplane 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 tnmrfyv;(9ql 6ej) gx7his field increase?

  16.47: Two small loops of wire are located close to a wirl)abz855psfk mwz fc+ /79ifzyhnv, 9rj mt:.e with conventional current directed up the page. Ahzbr8fv:m, 5zai+ f)kms/np wj.9 t57yc9zlf 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?

  17.35: A metal bar is movin*rfbg2ayar: t (*t r6tg to the left across a set of frictionless conducting rails as seen in the figure. fbag(r*rt2 y6tr*a t: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 shown?

  08.50:. An infinitely long solenoib+j nbgy.. g/q u1 md:ea*vwkk; 0b;9l,pds uhd passes through the circuit as shown. The magnetic field. yanqw ; vm :+buudkskg,01p*b/gb;l9h e .jd of the solenoid, directed 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 plaxdl5bzc;t(c . g7- idpavq(nh85e*d une 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 ideadvhbqccep;t( 7u8 i*55agzdl nd-.(xl voltmeter connected to the corners through the center of the loop. What is the magnitude of the voltmeter’s reading?