95.26: Two positive poi,ivac9*- o dolnt charges repel each other with force 0.36 N when their separation is 1.5 m. What force do thld-a 9*ov ic,oey exert on each other when their separation is 1.0 m?

  12.13 Approximately how many electrons must be removebr1t lv4tv0v;yjs1; gt gl 9l2d from an electrically neutral object toyt v921;1gr0v s;bjlgl4l vtt give it a net charge of Q = + 1.00 C ?

  13.15 In a circuit, the flowp;8us.hbn4e w of electrons in a horizontal wire produces a constant current of 3.20 A for a time of 3.0 hour. Which one of the following choices best r s8uhwp.;b 4neepresents the number of electrons that pass through a vertical cross-section of the wire during this time?

  13.07: Two identical particles are fixed in t5ik7tejw,5 zxr7*d zplace a distance of 0.50mapart. The electric force that one particle exerts on the other has a magnitude of 3.00 j kz*rt z5e5 t77iwdx,N. Which one of the following choices best represents the magnitude of each particle’s charge?

  07.25: If two protons are spaced by a distance R, what is the ratio of the 35tqaiw- da+s nl.3xg gravitational -qa533dsig awxl. +ntforce 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 m, x1dqoczp72f 2gp4t nass 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 describes the object that experiences the greatest magnitude of electric force from the other and which object experiences the greatest magnitude of221tc fgpzqx4n7o dp , acceleration? Ignore gravity.

  94.39: A small object with charge q and weight mg is wh0 6n9ubn98ab f jv:kattached 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 the presence of the field, the string makes a constant angle q with the vertic: jn9fbh0 8kuwa9 vb6nal. What is the sign and magnitude of q?

  09.38: A small object of mass M and charge Q is/fi 2aw( (h/.ej :zkwz wqr8bk connected to an insulating massless string in a vacuum on Earth. A uniform electric field exists throughout the region of the vacuum ( q(.//bk iwejhar2f:wwzzk8as 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 best indicates the trajectory of the mass?

  13.29 Two electrons entn16 xw z ssv95mv* sm+0gt-ahver a region between charged capacitor plates with equal speed v. Electron A is directed horizontally to the l 5hazx+1sv0 n-9 vs tmmv*s6wgeft 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 on a negative poi1m g+).c-iqc pmzx1 lsnt charge placed a distance x away. If the distance bet mcg1cq+1mi- .lpzsx)ween the two point charges 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-likeg,q 1/a mq5h rla0i0nt objects are separated by a distance R, the force between thl tra0g10 ima/,q5 qnhem is F. If the distance between them is quadrupled, the force between them is

  03.18: Two identical electrical pc2xc /dp2 iqea6kut t4rf16n0sbl -l)oint charges Q, separated by a distance produce an electrical force ofF on one another. If the distancernl 6tacb/ 2sk) t l621-e pucxqi4df0 is decreased to a distance of 0.40, what is the strength of
the resulting force?

  96.34: A point charge +q it0cgu:4y b12h,33o + 7vulxbwptn jrss placed midway between two point charges +3q and -q separated by a distance 2d. If Coulomb’s constant is k, the magnitude of the force on the charge +q b rn0t3vy3+7jcbth1up 2x4:,og lw us is:

  01.31: A positive poin 5qu2cni(ic4 gt charge of +q and a negative point charge of -q are separated by a distance d. What would be the magnitude of the electg2 u(n ccii4q5ric field midway between the two charges?

  08.33: Two point charges are fixed on the x-a q8icf54 5lqvyjw9:v+vz +vyaxis inotherwise empty space as shown bv 5y y+qvlviwc +9:jq48vfaz5 elow.
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 ar(h( 3./(52jj uohqg tljkrpyfe fixed on the x-axis in otherwise empty space as shown belohj/j( (h2g p u.3fjq5ryt(oklw.
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 accompany/yoyye )vv dh5l n.dfo3 *,dj(ing diagram. A nod/ d*3,voydj)hye(f l5y .vt which of the labeled points is the field most nearly zero?

  98.30: Four positive point charges are arrangjx p+0 ,f+tfxwq69ovl. nrlq 2ed as shown in the accompanying diagram. 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. The0++xljq p , wr9 qvf6n.oftxl2 magnitude of the total force on charge 3 is most nearly

  94.08: A point charge of +4.0 μC is placed faicv3 hn335l;: s 1oyegys)zon the negative x-axis 0.20 m to the lzas:y3 o1 f;s)3ygvlci e5nh3eft 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 the origin. The net electric field at the origin is zero. What is q?

  95.36: Assume the electric potential is zero at infinitti05 i 7fuijznm7 vsl7b23z,o y. 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. A second pm 77 i nizi7slbv5z0 3tu2o,jfoint 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 arranged on the corners of a 1x4k9+y+f n vd2 ggt: c-lhs(w) y9ikxa0 cm square as shown. What woulka+ f:9h-s4 xg)2 i(9kvwg+tnxcl dyyd be the direction of the resulting electric
field at the center point P?

  14.10: Two charges −Q and +Q, are fixelehx 2busk3 wq1 ii*h ft9ut-+s1.d-pd in place on the x-axis, each a distance a from the origin as shown. At the point labeled P, a distd+hh-et1u. u3 q91-i xk2pil* bfswtsance 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, +Q, +Q, and −2goo hd(d14nk+v qhfggo)020fQ, which one of the follow2gh+0h( 1 dfgnok 4d)vo 0fogqing choices best represents the direction of the electric field at the point P and the sign of the electric potential at P from these charges?

  17.43: A semi-circle has radi9.bb5 im,rtw hxqzf7 * sw1mi.us R, total charge Q, and a charge per unit lengt* whq f.1 x wbri,97i5zbmsm.th 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?