09.18: A wire has a conventional current I directed to the right. At the it 7 ,l;iudonc(w*js7lmr0gi3nstant shown in the figure, an electron has a velocildlnio3s7 7 0wtrug(mj; c*,ity directed to the left. The magnetic force on the electron at this instant is

  14.24: For the bar magnet 13g: .ivjfvdx shown in the figure, which choice best describes the direction of the magnetic field at the point P located directly abidfjv31: vxg. ove the center of the magnet?

  11.34: A wire lies in the +hwfii kf2+.i plane of the page with conventional current I shown. At the instant sh ifhfiw +.ki+2own, 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 d+e:dxchp8 :n u dpn/;mkz ndi*)08a pin a wire as shown. For the proton moving toward the top of the page at tn/ :udcz8ap;ni hm*xd0kd+n:de)8p phe instant shown, what is the direction of the magnetic force on the proton?

  94.30: The conventional current I in a long straight wire flows in the u95/p2q zxb5wr8r zspd 6u 5bwm:lvogeny ;,j)pward direction as shown in the figure. (Electron flow is downward.) At the instant a proton of charged5znw5/x)9r:esbrw b,u;ozp2g5pl m jy8q6v +e is a distance R from the wire and heading directly toward it, the force on the proton is:

  95.16: A charged particle with c f0:y elcko.:oonstant speed enters a uniform magnetic field whose direction is perpendicular to the particle’s veloceyk.of:cl :o0 ity. The particle will:

  98.10: A charged particle with constant velocity enters a 3rg+ev k05f1b 4xp7smi +bz1 twcm,,hl ohce 0uniform magnetic field whose direction is parallel to the particle’s velocity. The particle wil41e be,x5i70hbf crho+1mlskp g0+ t 3v,zwcm l

  03.34: A positively charged particle of mass M is at rest on a table. A non41dsa h2hfu *o- 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 the ele ad *4huho1fs2ctric force on the particle $F_E$ compared to the magneti force on the particle $F_B$?

  16.24: A proton moves with constant no :3z7st*xguuiz/np 75pow.k on-zero velocity in a region of space that has a uniform magnetic fiusoi7 upw *:px/g7tz3ko n5 .zeld 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 in this region of space? Ignore gravity

  04.14: A positive electric charge of negligible weight is released from rest 1usm b2 ,oer l6njwv)bd8 p0*lbetween the poles of a horseshoe magnet as shown. What would be the direction of the acceleration of the charge b8 1j0s 2l)uv *do6rnb ,mpewlcaused by the magnetic field?

  10.26: An electron moving in the plamg;g/tp 6vy a ja.u+:ine of the page at 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 g+:v.m;/pu gt aa6jy ithe instant that the electron enters the magnetic field, which best describes the direction of the resulting magnetic force on the electron?

  11.29: An electron moves with bo. cc+bjlv4.5teyk 7speed $1.00× 10^3\: m/s$ 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 trx3vl1/y7-- hm2phsiix ij un4avels at a speed v in a plane perpendicularvmph/u4yii7 x1- hlx3in2j- s to a magnetic 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, rpc. tzlm *4t;mass m, and speed v enters a magnetic field B and is deflected into a path with arl.m *t;ztcp4 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 zk .u jq9o9 pwm*hml(1l /cl-ma uniform magnetic field B. A helium nucleus moves in a circular orbit in the same magnetic field. If each particle (h.-lm kmm*qczo u1j/p99wllexperiences the same magnitude magnetic force during its motion, what is the ratio of the speed of the helium to the speed of the proton?

  10.43: Two ions travel perpendicular to the same uniform magnetic)m1. byjkahxlc 6u 5o2 field. The ions carry the same charge and have the same path radius in the magnetic field. Which of thel 1)a6 h2yxj5umb.cko following quantities must be the same for the two ions?

  02.15: A positively charged particle moves to the r,;ocmkqe* 2 dmight. It enters 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 m,2oqc e*kd;m constant velocity?

  96.40: A proton of massjjt1 zx r:2t5dxrm89g M and kinetic 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 el j5t(mwn+o*zpox33x;j yx njj;0v7 q uectrically charged beta particles is commonly determined byo( yq3mxnxj*jj0x+vu3 5pt 7;w zjo;n

  09.27: A proton moves straight up the plane of this page into a region he d7p(c *vv86 jz0 g.ipiii*kthat has a magnetic fivhk*i.pz7c( *ejgi6 id 0vp i8eld directed to the right. If the particle is undeflected as it passes through 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 two regions ofqb 6ocmhi c+psrw e/21v *.(ke space along the dotted-line trajectory shown in the figure. There is a uniform electric field in Region I directed into the plane of the page (as shown). There is no kvs1cw(pmrio 2+e* .be6/qchelectric 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 constant velocity through a region ofb r7) bc*jybn7 space containing y)n7 bbbj7*c rboth 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 non-zeea1qzsnvc1(y u a61us;vx* )cgs.gn) ro 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 e(yc1*snua1zx 6 u )sv.gva1)g cq;snexist at the location of the electron? Any electric field in the region originates from an unseen external source.