09.18: A wire has a conventional current I directed to7vxulmn y6)1j y rxkx/o+1e 0f the right. At the instant shown in the figure, an electron has a velocity directed to the left. The magfe )7yj1mo 0yux/lrv 6+nkx1 xnetic force on the electron at this instant is

  14.24: For the bar magno*zuu5f:y( eq et shown in the figure, which choice best describes the direction of the magnetic field at:oq 5zefuu*(y the point P located directly above the center of the magnet?

  11.34: A wire lies in the plane of the page with conventi1:x uf b6 itak+mr:vp(9ne c (j50yoezonal current I shown. At the ins yb(mfoejpu0:+kev :cnxi9t6ra1(z5tant shown, what is the direction of the magnetic force on the electron that is moving directly to the right toward the wire?

  13.30: Electrons flow to the left in a wire as shown. For the proton movi(hp m de,y709 x)fnz d5twu5ubng toward the top of the page at the instant shown, what is the direction of th )z7xb9hf5wduundp,0 yt(5 em e magnetic force on the proton?

  94.30: The conventional current I in a long straight wire flows in2l,1qfekokr h+7;d qif2b0s p9)dg pq the upward direction as shown in the figure. (Electron flow is downward.) At the instant a proton of charge +e is a distanc1o9s b7hp)g2pq0lq2irfqek dfk,+d;e R from the wire and heading directly toward it, the force on the proton is:

  95.16: A charged part8pf,m m8-alf eicle with constant speed enters a uniform magnetic field whose direction is perpendmla,m8 f- p8eficular to the particle’s velocity. The particle will:

  98.10: A charged particle vaups 9s-yi(ix:ppq,/;u2 jkwith constant velocity enters a uniform magnetic field whose direction is parallel to the particle’s velocity. :2ju-qv s p pyisa(9, ;xpku/iThe particle will

  03.34: A positively charged particle of mass M is at rkqa(ada f, -/iest on a table. A non- zero electric field E is directed into the plane of the table. A non-zero magnetic field B is directed out of the plane of the table. What is true about the magnitude of aqai-/(, kdfathe electric force on the particle $F_E$ compared to the magneti force on the particle $F_B$?

  16.24: A proton moves with constant non-zero velocity in a region iwvdyj:-p/ a5;;d m afof space that has a uniform magnetic field directed into the plane of the page. The proton moves directly up the plane of the page. What is the direction of the electric field af-yad5mjd ipv;/:w; in this region of space? Ignore gravity

  04.14: A positive electric charge of negligible weight is releascgkdj8 6v- 8yhed from rest between the poles of a horseshoe magnet as shown. What would be the direction of the acceleration of the charge caushc- jgv8k86yd ed by the magnetic field?

  10.26: An electron moving in the plane of the page atbws+6i5p;eaqogda nh o.oy e3/f,q . 6 an angle of 300 to the horizontal enters a region with a constant magnetic field directed horizontally in the plane of the page as shown. At the instant that the electron enters the magnetic field, which best describes the direction of th a+56ow ,g pn3; b6 fiod.ho.ayqee/sqe resulting magnetic force on the electron?

  11.29: An electron moves i7j0 u+9uhvc9ho 1naewith speed $1.00× 10^3\: m/s$ as it enters a region of space that has only a uniform magnetic field. The electron is accelerated because of this field with a constant magnitude of $8.00× 10^5\: m/s^2$ for the entire time of $1.00× 10^{−3}s $ that it is in the field. With what speed would the electron exit the field? Ignore gravity.

  14.29 An electron with charge −e and mass m travels at a speed v in a *m+fd go j44gra,ki n1plane perpendicular to a magnegg+if adrm, 4*14jo nktic field of magnitude B. The electron follows a circular path of radius R. In a time t, the electron travels halfway around the circle. What is the amount of work done by the magnetic force on the electron in this time?

  97.28: An ion with charge q, mass m, and speed v entersf3ucp. o7lm.59ab lqk a magnetic field B and is defla. 9lckbmqu7o p5 3f.lected into a path with a radius of curvature R. If a second ion has speed 2v, while m, q, and B are unchanged, what will be the radius of the second ion’s path?

  16.44: A proton moves in a circular orbit in a uniform magnetnvn vd; zd312fic field B. A helium nucleus moves in a circular orbit in the same magnetic field. If each particle experiences the same magnitude magnetic force during its motion, what is the ratio of the speed of the helium to the speed 2d ;fvz dv1nn3of the proton?

  10.43: Two ions travel perpendicular to thgre (* i+rytr/; 2vztme same uniform magnetic field. The ions carry the same charge and have the same path radiusye(;/+ 2ir *vt gzrmtr in the magnetic field. Which of the following quantities must be the same for the two ions?

  02.15: A positively charged particle moves to the right. It entersh*fhwnj5sd4jp,a u+7 a region of space in which there is an electric field directed up the plane of the paper (see figure). In which direction does a magnetic field have to point in this region so that the particle maintains a constant veloc ws p4dhf*j7 u,nj5a+hity?

  96.40: A proton of mass M and kinetizayifn7 s(-0 z3g 8fsmc energy $E_k$ passes undeflected through a region with electric
and magnetic fields perpendicular to each other. The electric field has magnitude E. The magnitude
of the magnetic field B is:

  04.25: The speed of electrically charged beta particles is commonly determiuu/r g:9z t:hrned bzh ut:9/r u:rgy

  09.27: A proton moves straightb0q()de -+c70; hvg gn ymo-1lttfzrlgdgk7- up the plane of this page into a region that has a magnetic field directed to the right. If the particle is undeflected as it passes through7 7gb+hye l cog) d(gnk-qz0 ;mvtf1 l-0dr-tg this region, in what direction must there be a component of electric field? Ignore gravity.

  08.36: An electron moves in the plane of the page through t5-k(ao e.g n8wm mw;rswo regions of space along the dotted-line trajectory sw w8a-g.m;(sn5r kemohown in the figure. There is a uniform electric field in Region I directed into the plane of the page (as shown). There is no electric field in Region II. What is a necessary direction of the magnetic field in regions I and II?
Ignore gravitational forces.

  12.36: A positive charge moves with hyy,2-gl nhc9constant velocity through a region of space con- y,g2ychh9l ntaining both an
electric field and a magnetic field. The electric field is directed out of the plane of the page.
Ignoring any gravitational field, which one of the following choices represents possible directions
of both the particle’s velocity and the total magnetic field in the region of space?

  15.29: An electron moves at constant nm p8x.gj rr17aon-zero velocity directly between two long straight wires. The conventional current in each wire has the same magnitude, but the currents are in opposite directions as shown in the figure. Ignoring gravity, which choice best reflects the direction of the magnetic field and the direction of the electric field that exist at the location of the electron? Any electric field in the region originates from an unsa7gx.m r81 jrpeen external source.