94.20: A magnet is dropped thro 8eu pml;+ony1ugh a vertical copper pipe slightly larger than the magnet. Relat1pu ;lyon+8meive to the speed it would fall in air, the magnet in the pipe falls:

  01.30: Lenz's law concerning tho-g cb:uk)hun-uz-/ue44 zw ze direction of an induced current in a conductor by a magnetic field could be a restatementuo -uzhw :zc4u)u- zn4b- g/ke of

  11.25: The product (3 Tesl 22mqjuf nlu9(.i lb(das) × (2 meters) × (4 meters/second) is equivalent to which ufmuljb 2.9qln(2d(i one of the following?

  04.34: A square loop is placed in a uniform magnetic fi.thm3+hw sapaj*p0 ;s eld perpendicular to the plane of the loop as shown. The 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 ;p+hpjaw at h*m3ss.0 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. Theyh ()dui;np1p.x xeb5 wire experiences an induced charge separation as shpiex; b .)d 5hyxpu1n(own. Which way is the wire moving?

  00.20: A wire moves with aqk, 6)hjr+ojn( bjgs:zn3fd. velocity v through a magnetic field and experiences an induced charge separation as shown. What is the dz3(rn .jgodsq)fjb,n 6h +jk:irection of the magnetic field?

  05.33: The figure below shows a bar moving to the right on twos myt o/yu ) )qxa:a72dsl3*li conducting rails. To make an induced current i in the direction indiysyaait 37x:sql*/l)d)umo 2 cated, 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 htsr8qc.43vgz8 1 jufje)l wf 0e 9bx9xas a voltage induced between the 8et blfe 3.4cj9xz)10r q9gfvwjs8 ux wire’s ends, 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 ccwswf/q;6 zc; onstant velocity 0.30 m/s traveling through a uniform magnew / cq6;swc;zftic 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 (t 4 q-sntfnb;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 negligibn qnt-;(stfb 4le 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 (w. hku:mzj7s,96 yspdtw3m5zl/ eomgn.5xl ; yhich 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 circui7m x l 5 ztsju6. :/hg3wmolek5sznp9,. my;dyt move in response to this change?

  08.29: A strong bar magnet is held very close to the openxr 5a8z /+sjkwing of a solenoid as shown in the diagram. As the magnet zsa5+jw/8rk x 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 circuit on the lea;d(jnmpph)f4 k m yg- 3l7z;aft 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 the resistor in the rightpa-g 4m;p 3(fj 7dm ynzahk;l)-hand circuit?

  10.39: A strong bar magnet is held vejuy;:*.b jt pcry close to the opening of a solenoid as shown in the diagram. As the magnet is moved to the left toward the solenoid, a conventi;j.cub*:t pyjonal 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 represent?

  14.34: Two circular loops oil5bx -+uc ,j s/8uns+agak4 xf resistive wire are placed next to each other as in the figure. The circular loop on the lus4 uab/lk -8,gjins5a c++xxeft 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 viewed in the figure from above)?

  11.41: For the figure shown, the variable resistance of)43o0 h wq2e(fyw xxsu 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 var2*h uon yme*g/iable 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 perpendicule+ 4j5cpfr: myar 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 effectefrm:4p j 5yc+s best describes the result of this field increase?

  16.47: Two small loops of wire are located cd7(tugn39 g5d )mya yalose to a wire with conventional current directed up the page. A scientist then moveg a)u9 d5dtyg(3nm7yas 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 moving to the leftol 8jto52dcv1 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 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 retljcv 8o125 odsistor at the instant shown?

  08.50:. An infinitely long solenoid passes through the circuit as shoe:frn-h;wwc v b)ei *3wn. The magnetic field ecw3- )ien b:f ;vh*wrof 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 plane of the page is decreasing in ti8gv(+y q e,yimu/ck +b g;su9fdjit, +me. 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 thri+ ,+gbmg ;eiqv(,c y+ j9ks/8fudtuyough the center of the loop. What is the magnitude of the voltmeter’s reading?