09.18: A wire has a conventional current I directed to the right. At the instangsc0 /wpo r:ed.m1u)r imlc7 1t shown in the figure, cw.1r/1m upg0e : )ri7msdcl oan electron has a velocity directed to the left. The magnetic force on the electron at this instant is

  14.24: For the bar magnet shown ul su.k*6b+axin the figure, which choice best describes the direction of the magnetic field at the point P located directly above the center of the magnet?aul* uxbs.6 k+

  11.34: A wire lies in the plane of the page with conventional current s4nq qc-fspp (t*ew- eai7:o* I shown. At the instant shown, what is the direction of the magnetic force on the electron that is moving directly to the right towa-:oes4cpt7*swae-np i* q qf(rd the wire?

  13.30: Electrons flow to the left in a wcc1w wh;jsifw+ +wl + eg-ufr5h*a*t;ire as shown. For the proton moving toward the top;c u*w5rc+ e- swifja;w1g* h+tlwf+h of the page at the 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 e ykq+ixdbk-.e9* h-m the upward direction as shown in the figure. (Electron flow is downward.) At the instant a proton of charge +e is a distance R from the wire and hea.9qy-mkk hxd-b*e +eiding directly toward it, the force on the proton is:

  95.16: A charged particle with constant speed enters *nh*sq3 8i ;bhwsty,ya uniform magnetic field whose direction isy s; q,*s3y*tbwn hh8i perpendicular to the particle’s velocity. The particle will:

  98.10: A charged particle with constant velocyci 9xx) bc1)7bh np8qity enters a uniform magnetic field whose direction is parallec9ync8)1b x7)h ix bpql to the particle’s velocity. The particle will

  03.34: A positively charged particle of mass M is at rest on a table. A non-nl +*i bta1hf1 zero electric field E is directed into at+ i1lh f*n1bthe 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 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 ony3:nvj bniy *,wq* 8yf space that has a uniform my*vyw b8i j,ny*:n3qnagnetic 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 in this region of space? Ignore gravity

  04.14: A positive electric charge ofjdr2*.nybuyve ;/0gq negligible weight is released from rest between the poles of a horseshoe magnet as showu.vdb y2qy */nj0 gre;n. What would be the direction of the acceleration of the charge caused by the magnetic field?

  10.26: An electron movk6 kb*,9ic y0k-ofx(/9cy* )jf ckdo tnyzu-ving in the plane 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 the instant that the electron enters the magnetic field, which best describes the direction of thfc kjz*kof t ,(ybouyn/ 9kc6v)k9-*c0 y-xdie resulting magnetic force on the electron?

  11.29: An electron moves with speed kpi . sg9+,ew gn5;z ptq)3bsv$1.00× 10^3\: m/s$ 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 trav6mr ysm3l. )yvu/) n ga3p1froels at a speed v in a plane perpendic)v gyf ypl3/um6armr)o1 s3n. ular 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 cha.8inue-1o ;;5hm ekwotg d tbhm.n:o2rge q, mass m, and speed v enters a magnetic field B and is deflected into a path with a radius of curvature R. If a second ion has speed 2v,nomw1d8m5 ;i;enok u2-hett ogh:.. b 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 magneq m;:g 82ki aem11,8rsub aehntic field B. A helium nucleus moves in a circular orbit in the same magnetic field. If each particle experiences the same magnitude magnetic force er 2uh8kg8 :mn 1,mba1;qa iseduring its motion, what is the ratio of the speed of the helium to the speed of the proton?

  10.43: Two ions travel pe3 yk bpa974k1sf-wf vr;j*y -c jsfp8nrpendicular to the same uniform magnetic field. The ions carry the same charge and have the same path radius in the magnetic field. Which of the j w1 9rssf ; yvf34apbjfc--yp*7kk8nfollowing quantities must be the same for the two ions?

  02.15: A positively charged particle moves to the right. It enters a region of dfh3 5.h;hsy0r0fzi xspace 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 pah;05z3xfh dy.rf 0s hirticle maintains a constant velocity?

  96.40: A proton of mass b; 4+g-q/.ng7ivbk kx0hpj0xzo-chn 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 electrically chjgz;)l* bob 8/ch:trwarged beta particles is commonly determined b c)b*/olhrzg;8bw :tjy

  09.27: A proton moves straight up the plane of this page into a 8*:okl a( maaeregion that has a magnetic field directed to the right. If the particle is undeflected as it passes through this region, in whatae:(k*a 8mo al direction must there be a component of electric field? Ignore gravity.

  08.36: An electron moves in the plane ofn.6 i1f:d duj22zblym the page through two regions of space along the dotted-line trajectory shown in the figure. There i2.yb un2jizd6 l:1mf ds 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 wit;g .n-u:le1yl4sggw fh constant velocity through a region of space containing both 4fel.nwsuy1g -: gg;lan
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-zero ve 31(f*hup6/az k-hovko k 2hbnlocity directly between two long straight wires. The conventional current in each wire fz k2pkh/ob* 6hu1nok ha-3(vhas 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 unseen external source.