09.18: A wire has a conventi8aa ek/a .2kwqonal current I directed to the right. At the instant shown in the figure, an electron has a velocity direc /.k82aae qwakted to the left. The magnetic force on the electron at this instant is

  14.24: For the bar magnet shown in the figure, which ch)fm3; p mht(uwoice best describes the direction of the magnetic field at the point P located directly ab uh3f(m )pt;wmove the center of the magnet?

  11.34: A wire lies in the plane of the page with conventional current,7kq xxzg:(k go-sy8 x I shown. At the instant shown, what is the direction of xgxxok kz, (q- :y7s8gthe magnetic force on the electron that is moving directly to the right toward the wire?

  13.30: Electrons flow to the left in7w .r nh+qntz/vy4 6 1q*youin a wire as shown. For the proton moving toward the top of the page at the instant shown, what is the direction yn16.on7izq h/4ywr*tnvu +qof the magnetic force on the proton?

  94.30: The conventional current I in a lo mfc716stj* fqhiv/1mazo.8l ng straight wire flows in the upward direction as shown in the figure. (Electron flom.l miq f/z1ha 6ts87vo1*f cjw is downward.) At the instant a proton of charge +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 constant speed enters a uniform magnetic fif a ;3e4a:qb/jzsbv;*xp:p xbeld whose direction is perpendicular to the particle:;e ;asj4bavp: *b q x/fz3pbx’s velocity. The particle will:

  98.10: A charged particle with constant velocity enters a unifo1bd;)r: xd 7hz fkmhj4rm magnetic field whose direction is paral7zj:hh)d;x mb1krfd 4 lel to the particle’s velocity. The particle will

  03.34: A positively charged particle of mass M is agmm32yao3/m l t rest on a table. A non- zero electric field E is directed into the plane of the table. A non-zero magnetl2mya33 om/m gic 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 constaki j5*nnq;3x7omj)qmf r) mi9nt non-zero velocity in a region of space that has a uniform magnetic field directed into the plane of the page. The proton moves direciqqkrj53nmo9n; mjx ))f *i m7tly 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 ofy*09fs y0(e)1jvuwgp2t0m x 2 r cszbn negligible weight is released from rest between the poles of a horseshoe magnet as s b sjry1xfz)* snp0myt 09e (0vu2g2cwhown. What would be the direction of the acceleration of the charge caused by the magnetic field?

  10.26: An electron moving in the plane of the pagv 0c s6q+ (shoes0pxf7e 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 elxh qs(v+0f soesp7c0 6ectron enters the magnetic field, which best describes the direction of the resulting magnetic force on the electron?

  11.29: An electron moves with s.efl9ybf en4*peed $1.00× 10^3\: m/s$ 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 chargmh8p4 qaoma:3/nv(4l ot 1 ciie −e and mass m travels at a speed v in a plane perpendicular to a magnetic field of magnitude B. The electron follows a circular pato1 a ht:v4 (3qcpil/o m4naim8h 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 chargftt2 o. 3v56k5qnu(kkdwan 5z umzm:+ e 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, while m, q, and B are unchanged, what will be the radius of ttkn5.uzzav wm5 ot(2qn3k65m kd+ u:fhe second ion’s path?

  16.44: A proton moves in l*iy7,sn t3i4 kkkf / nhw2iv(a circular orbit in a uniform magnetic field B. A helium nucleus moves in a circular orbit in the same magnetic field. If each particle exiihv,*w/n f( k2ny4l7kk3 s itperiences 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 magnetif j3*-;xs i ygix2bow1c field. The ions carry the same charge and have the same path radius in the magnetic field. Which of the following quantities must be the same for ; f3-byxio *j 2wgix1sthe two ions?

  02.15: A positively charged particle moqy.qqqmo xu/ 6 t0;wc(ves to the right. It enters a region of space in qtx qu0c/om w(y6q ;.qwhich 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 velocity?

  96.40: A proton of mass M and kine3hh3gsu /c 0qx+uflngi d1 n*hi+k 38ttic 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 elecxdubqh5-hwf a .,3,rovl-x g0trically charged beta particles is commonly determined byvl5ubaw dhrx h-,,f g.ox-3q0

  09.27: A proton moves straight up the plane of this page into a region that has5*s f, hg:a7e, x:h-enpdxqqa a magnetic field directed to the right. If the particle is undeflected as it passes throug,q ens da5fqhx::p *eg7ha-x ,h 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 regn5xkf49 t ek-xions of 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 electric field in Region II. What is a nece9t 5xf4exn k-kssary 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 of spaiv n(dc5l:8gv 15yef nce containingyfncniv:558gel(1 vd 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 non-zero velocity :g)c-nkhl4tyjxrs:3 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 i:n)sx ghjc:l rt y-4k3n the region originates from an unseen external source.