95.26: Two positive point charges repel each other with force 0.36 N when8s1yvqxlo 9mt+jc e*)dp s h7o9rgs6 5 their separation is 1.5 m. What forq ss 1xydvcojsmepor+gt65*l 89 )9h7 ce do they exert on each other when their separation is 1.0 m?

  12.13 Approximately how many electrons must be remov-c a8 gr;(wpj 8db b:-0cletafed from an electrically neutral object a0 cwgtplb(cf -8 dbea-: r;8jto give it a net charge of Q = + 1.00 C ?

  13.15 In a circuit, the flow of electrons in a horizontal wire produbhhip)c4ta,3gb3 l:m ces a constant current of 3.20 A fo hb3b) m3pc, gait4:hlr 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 are fixed in place a distance of 0.50mapm;,;tsowsehy0 d o 0xkl 2th16art. The electric force that one particle exerts on the other has a magnitude of 3.00 N. Which one of the following choices best represen;xd o ;tot1e0,s60w2 hl hskmyts the magnitude of each particle’s charge?

  07.25: If two protons are spaced by a distance R, wha0v/nljnn9f9dm nw n e6.:,xjft is the ratio of the gravitational forc6jejn9x 90lnvd: /wnf .fnnm,e 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 chargqjc z//.o xs(te Q and mass 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 of acceleration? Ignortxqco/js/z. ( e gravity.

  94.39: A small object with charge q and weight mg is attacr.7 a4lnwuk 2(bvf +yohed to one end of a string of length L. The other end is attached to a stati+bvwn k4yl 7aufr (.2oonary 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 chary /beyki*yzagy; iu+20 vb)e(2o+dmjge Q is connected 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 remains in static equilibrium at an angle of θ with the vertical as shown in the figure. When the string is cut, whicbio2yyebd ()0/u yaj 2;y+z vek+*g imh of the illustrated paths best indicates the trajectory of the mass?

  13.29 Two electrons enter a region between charged capacitor plates weh88ox6 n 6w pwax-l:yith equal speed v. Electron A is directed horizwnly68xo a-h :6pw ex8ontally 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 on a negative jmb4h 5/vu,a(sdj+wv point charge placed a distance x away. If the distance between the two point chargesa j(4vvwjb5ud s ,+h/m 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 /z2xtd2bygk,ol y*j:objects are separated by a distance R, the force between them is F. If the distance betw*y2k l:b o,2tjzgd/ xyeen them is quadrupled, the force between them is

  03.18: Two identical electrical /0 5bxway4 rgzobw(5 x*bqgd3point charges Q, separated by a distance produce an electrical force ofF on one another. If the distance is decreased to a distance of 0.40, what is tg(d g wx 5b03/ow4bb5zqxay r*he strength of
the resulting force?

  96.34: A point charge +q is /ulk2tllm ,v(placed midway between two point charges +3q and -q separated by a distance 2d. If Coulomb’s constant is k,utll,( 2lk vm/ the magnitude of the force on the charge +q is:

  01.31: A positive point charge of +q and a negative point charge of -q are r7jpfym: szheh3kxb 3+3o 1 x-separated by a distance d. What would be the magnitude of the electric field midwao rbh17mjsk-xef: zy ph+ 3x33y between the two charges?

  08.33: Two point charges are fixed 3p8 imysd36 oxon the x-axis inotherwise empty space as shown below.x y6383osdmpi
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-axis inoo2ytzw)6czv4y ;(kk otherwise empty space as shownok 2z vtk6wzy;) oy(4c below.
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 dbeln0nh,u-wfmi0g,-vo/v -y iagram. At whny-,m vhv-/o0lfu, b i-0 gnewich of the labeled points is the field most nearly zero?

  98.30: Four positive point charges:i/+ ido,l axl2 ur9bz are arranged as shown in the accompanying diagram. The force between charges 1 and 3 is 6.0 N; the forcez ri/i,2 a9:obdulx l+ 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 on the negaetyq.-o9 1)n v uy/u5ctz;ejztive 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 theeu yz ;.y95 cne /u1to)jqtv-z 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 potwm.kwd8)o bhxm5 w00 uential is zero at infinity. A point charge of +4.0μC is placed on the negativwxmmw0d wk0 8h5ub .o)e 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 charges are arranged one o68ubcj nb41av-8nh the corners of a 10 cm square as shown. u8 hc1a 8-b6bjnoven4What would be the direction of the resulting electric
field at the center point P?

  14.10: Two charges −Q and +Q, are fixed in place on the x-axis, eacdq+ r e9(*ju;uv s-zxsh a distance a from the origin as shown. At the point labeled P, a distance along they-axis from the origin, what is the direction of the electric fuvu+-ds( rs;e qz9j* xield from the given charges?

  16.33 Given the configuration of three charges, +Q, +Q, and −2Q, whichu59*le /mcmng1lrx *j one of the following choices best represents the direction *9glr5ljx*/u c1m emnof 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 radius R, .san1 ;2sa6g1garavw total charge Q, and a charge per unit length given n1 ws;2.aa1sg6aragv 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?