95.26: Two positive point charges repel each other with fo m6rk xm22xlq*y;f2 xnrce 0.36 N when their separation is 1.2xrkm; mxy6xfn 22* lq5 m. What force do they exert on each other when their separation is 1.0 m?

  12.13 Approximately how many electronsa p4)gnpwfl+aol, (q7 must be removed from an electrically neutra)+ agp, 7lp4aqofnl(w l object to give it a net charge of Q = + 1.00 C ?

  13.15 In a circuit, the4e bdli94zxd9c)7fiq flow of electrons in a horizontal wire produces a constant cldx dz cf94i)e79 bi4qurrent of 3.20 A for a time of 3.0 hour. Which one of the following choices best represents the number of electrons that pass through a vertical cross-section of the wire during this time?

  13.07: Two identical particles ar+ww 6z 2zt.tkce 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 wwctk .2 z6tz+choices best represents the magnitude of each particle’s charge?

  07.25: If two protons are spaced by a distance R, what is the rancs :tnrxb9*b(8l 7frtio of the gravitac( t*8:xsbl 9fn 7rnbrtional force 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 2cx54 jw 2l8zzqurqv(;3jn rxexperiment with a proton of charge Q and mass M being placujz 2(3xrrx q;c wj528qlnzv4 ed 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 describes 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 attaz tomv2 :9.luhched to one end of a string of length L. The other end is attached to a stationary support. The system is placed in a uniform horizontal electric field E, as shown in the accompanying figure. In th.uvzt9hm :2l oe 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 to an5a )ow-uqberp0qn3yt(ng5.io k z7) i insulating massless string in a vacuum on Earth. A uniform electric field exists throughout the region of the vacuum as indicated. The mass remains 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 b7e5g.3nn w-)a ob(pk 5z)yiq0 u itqroest indicates the trajectory of the mass?

  13.29 Two electrons enter a region between chargab*yiqo d: v-.pa pl 9mpk-;-sed capacitor plates with equal speed v. Electron A is directedy;mvi- pqasd9-. opak- l:*bp horizontally to the left while electron B is directed 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 point charge exerts a force of magnitude F;r whr*xw399ig1 wiuv on a negative point charge placed a distance x away. If the distance between the two point charges is halved, what is the magnitude of the new force that;ugrw91r 9iw hxi* wv3 the positive point charge exerts on the negative point charge?

  98.08: When two charged point-like objects are separated by a dcxcm-0 (vujpg6vtf 12 nk :j2aistance R, the force between them is F. If the 6 2nvc-0jktmf:pu1x2ca v j(gdistance between them is quadrupled, the force between them is

  03.18: Two identical electr fuu is3/coh.-ical point charges Q, separated by a distance produce an electrical force ofF on one another. If the distance -u3ichu/f.os is decreased to a distance of 0.40, what is the strength of
the resulting force?

  96.34: A point charge +q is placed mid4zu yoy 3,4qs8zd *ycc/ou ky/way between two point charges +3q and -q separated by a distance 2d. If Coulomb’s constant is k, the magnitude y/zu8c u4sy*4dzk,qcyo/y o3of the force on the charge +q is:

  01.31: A positive po rgv8yj/hx)f6 int charge of +q and a negative point charge of -q are separated by a distance d. What would be the magnitude of the electric field midway betw8r jh)y xvgf6/een the two charges?

  08.33: Two point charges are fixed on the x-axime5mq;ibfze7wrz1dn(hp64) , iqh)f s inotherwise empty space as showfrm meh )6b5 i1fe(d),4;w7qphi q nzzn below.
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 are fixed on the x-, pmm(fn ,s8jsaxis in otherwise empty space as shown belopsjsnm8(f , m,w.
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 arranged as shown in the accompanying d3 c5g-i ejo5yqi(r o,kiagram. At which of the labeled points is the field most nearly zej -3okqec5yi, i5(orgro?

  98.30: Four positive point charges ard9ho( sz z2k3pe arranged as shown in the accompanying diagram.zkd3p s o9(2zh The force between charges 1 and 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 z, ref1b-p omp-ve-z/of +4.0 μC is placed on the negative x-axis 0.20 m to the left of tfp/mzpeob--1zv ,r -ehe 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 the origin. The net electric field at the origin is zero. What is q?

  95.36: Assume the electric potential is zero atbwx,( biq88g8sky a6 z infinity. A point charge of +4.0μC is placed on the negative x-axis 0.20 m to the left of the origin, as shown in the accompanying figure. xgyb6 (ik 888bzsaw,qA 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 charges are arrahff9 9zpt9ne 7nged on the corners of a 10 cm square as shown. What would be the directi97 n99f fepthzon of the resulting electric
field at the center point P?

  14.10: Two charges −Q and +Q, are fixed in pb;( lmtfeh43vlace on the x-axis, each a distance a from theelht ;(vb34f m origin as shown. At the point labeled P, a distance along they-axis from the origin, what is the direction of the electric field from the given charges?

  16.33 Given the configuration of three charges, 8bt*d,wq phfgm 65a+p+Q, +Q, and −2Q, which one of the following choices best represents the direction of p6tfbad*hqw 8+ 5,mpgthe electric field at the point P and the sign of the electric potential at P from these charges?

  17.43: A semi-circle has radius ptra k:2l2e+nR, total charge Q, and a charge per unit lengtn2preal2 :k t+h given 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?