94.20: A magnet is dropped through a vertical copper g:ji y y/0oh6vpipe slightly larger than the magnet. Relative to the speed it wouldjvi /:oyy6g 0h fall in air, the magnet in the pipe falls:

  01.30: Lenz's law concerning to ofcwznn5//u4 nq+4che direction of an induced current in a conductor by a magnetic field could be a res45 /n /+n4foqzcwocn utatement of

  11.25: The product (3 Teslas) × (2 iguwzhi13y(45 nff zwj/ez/* meters) × (4 meters/second) is equivalent to which one 15y3zwi j*u4 fn/ ghi(fzz/ew of the following?

  04.34: A square loop is placed in a uniform magnetic field perpendicular to x2s:x / cm c/hhdyy)q*the plane of the loop as shown. The loop is 0.5 mexqc y/)*hxh m/ :csyd2ters 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 magw b)vl2yk*k .onetic field directed into the page. The wire experiences an induced charge separation as shown. Which way isyok. *2bv)lwk the wire moving?

  00.20: A wire moves with a v qoi k 6hz,c9tuw+; zb*k17vmielocity v through a magnetic field and experiences an induced charge separation as shown. What is the direction of the magnetic h67kvziztw o9uq+i1, kc; m*bfield?

  05.33: The figure below shows a )az8a:1h)tasm- tfvn bar moving to the right on two conducting rails. To make an induced current i in the directiont n s )f1avah:am-)zt8 indicated, in what direction would the magnetic field be in the area contained within the conducting rails?

  00.10: When a wire moving through a magnetic field has a voalra3 5tbt 1e6ltage induced between the wire’s endsab361t5 lrate, that 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,.: xtw 8fdydn xn9+zj 0.30 m/s traveling through a uniform magnetic field of 0.060 T. The rod, velocity, and magnetic field are all mutually perpxwz df+xt j:8n9dy.,nendicular. What is the potential difference induced across the rod’s length?

  04.42: A solenoid is oriented en bqnw5)idt-d4 o2;sr7ayxybkaackx9, ;32 c hd-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 cok3tb wk ;qy5canc)sio hy 2d4xx-a ,r72abd;9ming 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 s5xmi p1su u0;(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 5u 1u0ipmx ;ssneedle 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 solenoid as rr2:ith4 y pjvg3--g m)b i2zoshown in thp gv h-r- )mi2oyz: gr42itbj3e 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 current?

  09.37: For the figure shown, the variable resistance in the circuvv 4d+y;:rj9knyl v ;eit on the left is increased at a constant rate. What is the direction of the magnetic field at the point P at the center oyd jre :yvv9l +4n;k;vf 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 o +j1tuu;mirsgueift:-+(du3h lt :9hf a solenoid as shown in the diagram. As the magnet is moved to the left toward the solenoid, a conventional current thiu;l jf(m tih:31hg9:sdeutt ruu++- rough 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 represent?

  14.34: Two circular loops of resistive wire are plab a,(9,k h6yo tfla,ajced next to each other as in the figure. The circular loop on the left is connected to a constant voltage source V. The rel,th jf,aay9 bk,(ao6sistance 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 viewed in the figure from above)?

  11.41: For the figure shown, the variable resistance of km7u7aqe /f :hthe 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 s6t7 o 5j) wcrufeox9o7rkc ,f5hown, the variable 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, conduct 1-bkqpps* f p6gz wzbybrv0z l4,4,r9ing 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 descy4gf,,z*-0zp6s 1brp zp brlvq4w b k9ribes the result of this field increase?

  16.47: Two small loops of wire are located close to a wire with vu8 ez3bgvf.d6 *vbi+conventional current directed up the page. A scientist then moves the loops away from the current as shown. What is the fb8bu z3i*v6v.dgv+ e orientation of the conventional current in each loop while this occurs?

  17.35: A metal bar is moving to z9t3a 39 ya:kxj p67la/ayzqz 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 pll9 qytj 7z y9z3aazaap/:6k x3ane 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 pas7b0uj;nu l8mqy pta7 *ses through the circuit as shown. The magnetic field of the solenoid, b;ptya7 m 7uq*ljn80u 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 theyti iq degs w42f/)e41 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 vsi e4y4q w1 )g2tfei/doltmeter’s reading?