95.26: Two positive poinhp7cnx*1zti;qjz(k79 l ;wy gt charges repel each other with force 0.36 N when their separation is 1. j7tk*cw nx ;9(qyg li7pz1hz;5 m. What force do they exert on each other when their separation is 1.0 m?

  12.13 Approximately how many electrons must be removed from an electrically neu1, 6yhumikb+*4zk qjbmne t 7+tral object to give it a net charge of Q = + b1yequ,+it z*b7m +n kj4mhk6 1.00 C ?

  13.15 In a circuit, the flow of electrons in a horizontal wire producey.d; ,4opbvrfs a constant current of 3.20 A for a time of 3.0 hour. Which one of the following choices best represents the number of d.f,vo br4;ypelectrons that pass through a vertical cross-section of the wire during this time?

  13.07: Two identical partic2hcf 7*on9yz7 zcrsk +7fu,mjles are fixed in place a distance of 0.50mapart. The electric force that one particle exerts on the other has a magnitude of 3.00 N. Which one of the following choices best represents the magnitudy 77c 79mu 2zjzn*rk fshf,+coe of each particle’s charge?

  07.25: If two protons are spaced by a distance R, what is the ratio of the fkz8.rx0 ) cqhn.ry8rrkz +z74v (ubegravitational forr 8krq.zrf7kv8nb4ex. 0hrycz )+z(u ce that one
proton exerts on the other to the electric force that one proton exerts on the other?That is,$\frac{F_{gravity}}{F_{electric}}$=

  10.12: A scientist sets up an experiment with a proton of charge Q and mas.v i* w3sikkly6 +ql+q u-r/fks M being placed near a helium nucleus (2 protons and 2 neutrons) of charge +2Q and mass 4M. The objects are each released from rest and begin to move. From the scientist’s point of view, which choice best descr*u +lv3/w.r6skil yq+ik- qfk ibes the object that experiences the greatest magnitude of electric force from the other and which object experiences the greatest magnitude of acceleration? Ignore gravity.

  94.39: A small object with charge q and weight mg is attack v:,zq vw;lbu5 19ztjhed to one end of a string of length L. The other end is attached to au5v;l: 9 jvz tkz,b1wq stationary support. The system is placed in a uniform horizontal electric field E, as shown in the accompanying figure. In the presence of the field, the string makes a constant angle q with the vertical. What is the sign and magnitude of q?

  09.38: A small object of mass M and charge Q is connected.guw jv.n m+k7 to an insulating massless string in a vacuum on Earth. A uniform electric field exists throughout the region of the vacuum as indicated. The mass remainvk.w g+.m j7uns in static equilibrium at an angle of θ with the vertical as shown in the figure. When the string is cut, which of the illustrated paths best indicates the trajectory of the mass?

  13.29 Two electrons enter/b.q:dkgyo-y)z5n8 jwmm 6nd ac+91f v/ tltr a region between charged capacitor plates with equal speed v. Electron A is directed horizontally to the left while electron B is dire/a lby+/5 r.-: nzo nj8)m96mygc1ddf ktwtqvcted at$30^{\circ}$below the horizontal. Each electron makes it to the left-hand plate. Which one of the following choices best compares the speeds of the charges ( $V_A$, $V_B$) upon arrival at the left plate? Consider only the electrons A and B’s interactions with the constant electric field between the plates, ignoring any relativistic effects.

  08.06: A positive poinkov4+h:d8jr095f7 sty o*m amv6jalz t charge exerts a force of magnitude F on a negative point charge placed a distance x away. If the distance between the two point char:z*a7y+ojv0d4m5hsmtl8 9 k jr6voafges is halved, what is the magnitude of the new force that the positive point charge exerts on the negative point charge?

  98.08: When two charged point-like objects are separated by a distance R, the fof, cwuh.ny(.l5*2i i gsaey4srce between them is F. If the distance between them is quadrupled, the force betw4,( a.ec wihys5nfi s2y*g ul.een them is

  03.18: Two identical electrical point charges Q, separated by a distancep 7f-:vq2s 8ddnwi-fg produce an electrical force ofF on one another. If the distance is decreased to a distance of 0.48 -i gp7fq-nvdw d:fs20, what is the strength of
the resulting force?

  96.34: A point charge +q is 28 c(pipj n34k5et d(z7esrvuplaced midway between two point charges +3q and -q sepadjr8 7 kp(ztiu 43e s5cvp(ne2rated by a distance 2d. If Coulomb’s constant is k, the magnitude of the force on the charge +q is:

  01.31: A positive point charge of +q and a negative pointyif7u/ 9:koe a(cse2q charge of -q are separated by a distance d. What y 7oisfa9 cuek/:e(q2would be the magnitude of the electric field midway between the two charges?

  08.33: Two point charges are fix -9(y td-clwlhed on the x-axis inotherwise empty space as shown below. -th(lw 9ycd -l
In which Region(s) is there a place on the x-axis (aside from infinity) at which the electric potential is equal to zero?

  08.34: Two point charges g(d2-j 2d vsod:srkw9are fixed on the x-axis in otherwise empty space as shown bgdws jvk2 (9:ddsro 2-elow.
In which Region(s) is there a place on the x-axis (aside from infinity) at which the electric field is equal to zero?

  98.23: Two charges +Q and –4Q are arralw79(j z6tasjr5t:u eu 2ll.hnged as shown in the accompanying diagram. At which of the labe9 jr.jh:ulttl65l 2sazw7e u(led points is the field most nearly zero?

  98.30: Four positive point charges are arranged as shown in the accompanyingcf* b 1a8i*md,dj2ach*iz tso9r:p3r diagram. The force between charges 1 and a9c1mi8dc,h 2 bj *zdr*otpasr3if*: 3 is 6.0 N; the force between charges 2 and 3 is 5.0 N; and the force between charges 3 and 4 is 3.0 N. The magnitude of the total force on charge 3 is most nearly

  94.08: A point charge of +4.0 μC is placed oe; ulnvl(9cw; .py4n4d ;zydwn the negative x-axis 0.20 m to the left of the origin, as shown in the accompanying figure. A second point charge q is placed on the positive x-axis 0.30 mto the right of n;; eyd9 ;4u zlncwpd.w(4vy lthe origin. The net electric field at the origin is zero. What is q?

  95.36: Assume the electri1xeoglzx9svjzy j)6o;ln44-c potential is zero at infinity. A point charge of +4.0μC xy)o 4 zj;-v6xl91l sz4jogenis placed on the negative x-axis 0.20 m to the left of the origin, as shown in the accompanying figure. A second point charge q is placed on the positive x-axis 0.30 m to the right of the origin. The net electric potential at the origin is also zero. What is q’s charge?

  03.27: Four electrical chajnr gs4/s,p t63zvzr: rges are arranged on the corners of a 10 cm square as shown. What wo/:,s g3znrrj svpz4t 6uld be the direction of the resulting electric
field at the center point P?

  14.10: Two charges −Q and +Q, are fixed in plaq h.cf0ynqmk w*3 ;oz4ce on the x-axis, each a distance a from the origin as shown. At the point labeled P, a distance along they-axis from the origin, what is the dirqn 4y3hmfc q.w;ko*0zection of the electric field from the given charges?

  16.33 Given the configuration of th/op +hg6n ,yi 6w*iug 9c8ew8g y ajzd*fu-4mrree charges, +Q, +Q, and −2Q, which one of the following choices best represents the direction of the electric field at the point P and the sign of the electrd/rj*-*8zgw9 6i6af, huy ggy e n8icowp+ um4ic potential at P from these charges?

  17.43: A semi-circle has radius R, total chargg+.xh(( ,rfqu 0l wuaee Q, and a charge per unit length g0euagr(xuw.(+fql , hiven as $λ=λ_0cosθ$ with θ defined in the figure and $λ_0$ a positive constant. Which one of the following choices gives the electric field strength at the point labeled P?