09.18: A wire has a conventional curre t*4kn8cc w0llnt I directed to the right. At the instant shown in the figure, an elnw4tcl8lk* 0 cectron has a velocity directed to the left. The magnetic force on the electron at this instant is

  14.24: For the bar magnet shown in the figure, , e 1uwvqik5w)which choice best describes the direction of the magnetic field at the point P locatikweq )vw5u1,ed directly above the center of the magnet?

  11.34: A wire lies in the plane of the page with conventional current I swwri pxl; h79mmhdp i.-n;+n:hown. At the instant shown, what is the direction of the magnetic i-i w .;;:+r mwmxp9nhndhpl7force on the electron that is moving directly to the right toward the wire?

  13.30: Electrons flow to to ,npqj9h08 fjiv1m x)he left in a wire as shown. For the proton moving toward the top of the page at the instant sho8)nqm91jv0ifho,xj pwn, what is the direction of the magnetic force on the proton?

  94.30: The conventional current I in a lonbns :s, 7 2hndtz ahjv;1)nrr.g straight wire flows in 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 2b rta ;v nshnj): .7znhd1,rswire and heading directly toward it, the force on the proton is:

  95.16: A charged particle with constant speed enters a z ui-;: ccgwr.uniform magnetic field whose direction is perpendicular to the particle’s velocity. The particle wwc:cru;z i-.gill:

  98.10: A charged particle j2e qjn 6nljq **+yg;iy2l 0vzquq7s3with constant velocity enters a uniform magnetic field whose direction is parallel to the particle’s vel yz32 7jj0lijqnq *g; 2 +ynle*6qsvquocity. The particle will

  03.34: A positively charged particle of8k+ w ;xy qse0a0.r(qynzk0ry mass M is at rest 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 the electric force on the partrsk0zer.0q +kwx8;y a(yyq n 0icle $F_E$ compared to the magneti force on the particle $F_B$?

  16.24: A proton moves with constant non-zero velocityuw1k53fi3qntv1cbht ; ks 0b ) in a region of 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 in this 10tkbqnwc3kvb5 f uih1s);t3 region of space? Ignore gravity

  04.14: A positive electric charge of negligible weight is released from resw7 oqw8fg;6d 08brj -(jxvn ; teit2ntt between the poles of a horseshoe magnet as shown. What would be the direction of the acceleration of the charge caused by the magd 7gb 8t(j2wwt-t6n;8; xjei0qv nrof netic field?

  10.26: An electron moving ia;b 65c1ze axnu.ciyrg/- d rm7 +nz3nn the plane of the page at an angle of 300 to the horizontal enters a region with a constant magnetic field directed horizontall7ci.+x1/y;zn6n 5 3a bm udrn-arczegy in the plane of the page as shown. At the 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 mo+-+am yey q i.l;dsq;2d yyj 5uzg*uu+k17uxnves with 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 plant)vf y(rcz(ly qd m42tb4,: moe perpendicular 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 v:mc lzy2q( 4dmytf) ob(r, t4the 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 enters a magnetgvaha u) reu,38qe0.l ic 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 bq)3a8. 0e,gvhaurue l e the radius of the second ion’s path?

  16.44: A proton moves in a circular orbit in a unip35 bo0d s7sstform magnetic field B. A helium nucleus moves in a circular orbit in the same magnetic field. If each7os st53d bps0 particle experiences 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 travelbf4hu8do/p uf o382hb perpendicular to the same uniform magnetic field. The ions carry the same charge and have the same path radius in the ma3bp4ubduf88 oh fh2/ognetic field. Which of the following quantities must be the same for the two ions?

  02.15: A positively charged particle mo;0hgpk0 lijp )ves to the right. 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 constant veloc0igk)hpp 0j;l ity?

  96.40: A proton of mass M and kinetic ene-0le v eya wmkdr6s3mu;l+9 +xa6a,umrgy $E_k$ 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 ele1:;nhmt xva; b0f sa;kctrically charged beta particles is commonly determined byxkmf; 0 ;:a;sbnt1v ah

  09.27: A proton moves straight up the plane of this page mnpz n7 jx z2v 7sxgi( d;):r4er4ds8linto a region that has a magnetic field directed to the right. If the particle is undeflected as it passes through this region, in what direction must there be a nm4x r;s:p 8lg4idd)zrej7 7zxn2 (sv component of electric field? Ignore gravity.

  08.36: An electron mj)wp + ah.jja1jd3z 2soves in the plane of the page through two regions of space along the dotted-line trajectory shown in thz)aps+ 2ajj1 w.jhjd3 e 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 mjp7tii6-k 5v constant velocity through a region of space containv5tkjm 7i6-i ping 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 atxd1 exql6,j1)enn8w m constant non-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 q 8xnee)xjn1 m1dwl ,6the 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.