09.18: A wire has a conventional current I directed to th7an,dccq v c7wn0r,z6 e right. At the instant shown i, ncwna7 dz0cvq6 7r,cn the figure, an 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 in the figure, which choice best df4 du ry. aw*jex2o)7)g+rx4 t-rez oyescribes the directio).+jyr ye x 4)2wa 4xdurgo to*r-e7fzn of the magnetic field at the point P located directly above the center of the magnet?

  11.34: A wire lies in the plane of the page witsnj. /ncn6 q,o4 6iw pfsgmfnc.+3e1uh conventional current I shown. At the instant shown, what is tcsmwgn4f+j63pocfu,1 6/ni .s qen n.he direction of the magnetic force on the electron that is moving directly to the right toward the wire?

  13.30: Electrons flow to the lefth f 0h23 ,uvph0il pob;9hbb3fibyn;) w61dbn in a wire as shown. For the proton moving toward the top of the page at the instant shown, what6 h h2i;l,3pyfbbn3 u n0ibvh1 w0dh b)pf9bo; is the direction of the magnetic force on the proton?

  94.30: The conventional curre c-u:pz8n-vda adnfb ;)d nh6yj-g5k/nt I in a long 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 wire and heading did -b;hna-u )k v/8af56zpnc :dgj ndy-rectly toward it, the force on the proton is:

  95.16: A charged particle with constant spee w up8it+:jgxvqx 1d;7d enters a uniform magnetic field whose :x8w;1gt 7pd ix uvjq+direction is perpendicular to the particle’s velocity. The particle will:

  98.10: A charged partihde ..pk a:si++ugsm,vcp*+ ecle with constant velocity enters a uniform magnetic field whose direction is parallel tp:km v,h+ec.ua.s++sed *ig po the particle’s velocity. The particle will

  03.34: A positively char f *ov(rmd7v*+ b1w (oir,ugkems,g(bged particle of 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 bgs me *(i kbdgvm,oo7(vwru1* +r,f(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 regionsu9)qn3 :rl nu/;aay ;+m bhmm of space that has a uniform magnetic field directed into the plane of the page. The proton s: ;muu na+/9lhq;) mman3rybmoves 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 electriptulfy6,: lx (c charge of negligible weight is released from rest between the poles of a horseshoe magnet as shown. What would be the di,p6(:xlu tylfrection of the acceleration of the charge caused by the magnetic field?

  10.26: An electron moving in the plane of the page at an angle of 300 tt6r8yqt c6/vl(w bvs+* fmm(co 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 oyb+crflvv s 8mc( t*/mq66 (twf the resulting magnetic force on the electron?

  11.29: An electron moves withxm/+f +z0iofyla9ew) 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 plane x/ lhbpul7cc *i /;u:pm0hvo7perpendicular 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 /im o/p l*;x phuchc7:u 0v7lbthis time?

  97.28: An ion with charge q, mass m, and speed v enters a mazgfoh / rsd*fovd,* 6 w-hi(a*gnetic field B and is deflected into a path with a radoi 6r a, ** wgddo-/*(zfhfshvius 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 w e)kj5xkqhl)z x/):xin a uniform magnetic 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 speed5)lj:ez)/qkxhx)kx w of the proton?

  10.43: Two ions travel perpendicular to the same uniform magnetic fiit6* l nh8nbu56uno8 neld. The ions cb*ni hn8 tn6unuo5l6 8arry the same charge and have the same path radius in the magnetic field. Which of the following quantities must be the same for the two ions?

  02.15: A positively charged particle moves t5qlhj9s.o yb78z )m neo 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 directihnyo89l z5 jsqb )7m.eon does a magnetic field have to point in this region so that the particle maintains a constant velocity?

  96.40: A proton of massf :due+.i wug3 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 charged beta particles is .emavx)zf5fxb6 s 3/a4t*nry commonly determined b)e rm.4fta*az sbvx6y3 f /xn5y

  09.27: A proton moves straight up the plane of this page into aa 80 nd8xln4e 8tic3qv region that has a magnetic field direct8xde3 val8840itn qc ned 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 aq*ac8n)hqvnv 1nxu n:w;u/(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 necessary direction of the magnetic field in regioncnn 1h/w8qxa vq);nuna v u:(*s I and II?
Ignore gravitational forces.

  12.36: A positive charge moves with constant velocity throuzcwel 9hqw+uj.) f6 (bduz1p)gh a region of space contu z) +ue(6bp)wcld9z q j.1hwfaining 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 conlk*g04 mh2tpystant non-zero velocity directly between two long straig klp*m04ht2gyht 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 unseen external source.