09.18: A wire has a conventional current I directed to tho4 s6x ntnnmtg v.z8s(,hu y5wt)*9gxe right. At the instant shown in the figure, an electron hay* ,sn.zmto xtx)( 9vusgw86g4n5nht s 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 bec:hjr*e f 906g 8umaq no;o3vust describes the direction of the magnetic field at the point P located directly abo qo6mnu8of:uea9;*cjvr3g0 h ve the center of the magnet?

  11.34: A wire lies in the plane of the page with conventi l1(cws+zi.fdo:l od- onal current I shown. At the instant shown, what is the direction of the magnetic forcelzo 1c-ls(o.fi:w d+d on the electron that is moving directly to the right toward the wire?

  13.30: Electrons flow to the lem5tc:s * p-tpwft in a wire as shown. For the proton moving toward the top of the page at the instant shown, what- tm:* wpcts5p is the direction of the magnetic force on the proton?

  94.30: The conventional current I in a long str o 2ey/)dscwu4aight wire flows in the upward direction as shown in the figure. (Electro/d4su e cw)2yon flow 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 magne rn,;(u9mfu- ytqf uy0cbw)g;tic field whose direction is perpendicular to the particle’s tgw n(quf9;;0 )yu mfcu-r,byvelocity. The particle will:

  98.10: A charged particle with consta(y 9 rjd *nm6ugp)gw-hnt velocity enters a uniform magnetic field whose direction is parallel to the particle’s velo(p g 9w-)*r6djn gmuhycity. The particle will

  03.34: A positively charged particle of mass M is at rest on a table. A non- ze59 iiw8,z 8lqsxq2oyvg .n p.oro electric field E is directed into the plane of the table. A non-zero o ilqv,z.gx8p8qo.59i ws yn2magnetic 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 :()qml 4ti, pxw5tuyyof space that has x:yw4yl5, ptium) ( tqa 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 region of space? Ignore gravity

  04.14: A positive electr2qor: lg:r-r,5spe f dic charge of negligible weight is released from rest between the poles of a o,2r-: q5pfr ldg:es r horseshoe magnet as shown. What would be the direction of the acceleration of the charge caused by the magnetic field?

  10.26: An electron moving in the plane ofvf/xziw iq1+.sj2x :0 sg q6gz the page at an angle of 300 to the horizontal enters a region with a c1xw6i2q gi:+/ z.gz0j q xsfsvonstant 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 the resulting magnetic force on the electron?

  11.29: An electron move)qmzs7kq.rrrq.a cq-6b iz 9.s 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 a an9 ,w oqwmwkfyo1:1.t a speed v in a plane perpendicular to a magnetic field of magnitude B. The electron follows a circular path of radius R. In a time t, the electronwmqy w.9 :noa1f 1,wok 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, mass m, and 5oxwz u11db)ad+t n9dspeed 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, andnzdw1x) 5d1uot+ ad9 b B are unchanged, what will be the radius of the second ion’s path?

  16.44: A proton moves in ,.7v /;evm odpexe*hy.pf ml0a circular orbit in a uniform magnetic field B. A helium nucleus moves in a circular orbit in the same magnetic field. If each particle experiences the same magnitu; e./v d0*m p mf.7ve,xylpoehde 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 trave2dl ccd z(dq*jq+ll8mir+:c/8p l9fsl perpendicular to the same uniform magnetic field. The ions carry the same charge and have the same path radir+:8dzs(8/q*9cdqpc l i+fm ld 2lcl jus in the magnetic field. Which of the following quantities must be the same for the two ions?

  02.15: A positively charged particle moves to the right. It enters a region of sev0n r 5y7cwfljm7. o)pace 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 plv7.eywmr 5)c no jf07article maintains a constant velocity?

  96.40: A proton of mass M and kinetic c:w+p liu*xs*cn4h 1oenergy $E_k$ 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 ce1s; wk;lc;q0bg22bqtj;g+s 8s ovk jommonly determined bkbqg cso8ew+l2 s;;sbv1qj jk0;2g t ;y

  09.27: A proton moves straight ::nhg cmz-a.n up the plane of this page into 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 tgz:n.: cm-ahnhere be a component of electric field? Ignore gravity.

  08.36: An electron moves in the plane of tho(w4n e1*7p) tqkuwll 3qb5mme page through two regions 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 fi75k1( q4n ul w3)o lqmtemp*wbeld in regions I and II?
Ignore gravitational forces.

  12.36: A positive charge moves with constant velocity through a rgxf) e2 3.dj hhnd08fhegion of space containing bojf h0dd8.ef gh nx3h)2th 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-zer;ogwhz c9m 8tqps80c+o 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 otm g0p z8;8+cwhq9 scfield that exist at the location of the electron? Any electric field in the region originates from an unseen external source.