95.26: Two positive point charges repel each other zmh 3j1x t0cj;with force 0.36 N when their separation is 1.5 m. What force do they e0j;jz th cx31mxert on each other when their separation is 1.0 m?

  12.13 Approximately how many electrons must be removed from an electrically netw/3 ,ry)h fbhutral obje t,)/rfw3h hbyct to give it a net charge of Q = + 1.00 C ?

  13.15 In a circuit, the flow of electrons in a horizontal ag x+,t5, xo8p3gq qzl9:qbdt7buvb g*ly /l /wire produces 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 electrons that pass through a vertical cross-section of the wire duringlt ox3t/lu 7b*gx a,q8gp5qd v:bq +zy9,lb/g this time?

  13.07: Two identical particles are fixed in place a dx ;tr07) kmgzkistance 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 choicz7 ktrmxk g0;)es 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 quq.deil737ql )1 dy p i4n(t1mh6fragravitationalrl pl73iy iqq4.( 6d1aqm1)h tdnufe7 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;j7htni 1zy 8+wnd:r m experiment with a proton of charge 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 viem ; w8yr7+zj1tn:di hnw, 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 weig9bpbcxj1q g,k d04 sow9; flf)ht mg is attached to one end of a string of length L. The other end is attached to a stationary support. The system is placewg 9cxblo49q s1dpf) k;,0bjf d 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 xay . a4 5(*y/y:bnu/htl diskmass M and charge 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 fi/a5ykynuxh (y :.4la*d/bsi tgure. When the string is cut, which of the illustrated paths best indicates the trajectory of the mass?

  13.29 Two electrons enter a region between cas6,yox1 qz7n) e hwz9harged capacitor plates with equal speed v. Electron A is directed horizontally to the left whwhzo s 9 xaqyz6,71n)eile 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 o5 yiw8lxv q1 giv m4w5cu-ohs+7.+gukf magnitude F 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 thaxv 45y +m+-wi.lqsh g75o81 gcuivkuwt the positive point charge exerts on the negative point charge?

  98.08: When two charged point-like objnb55 k4,xnq thfy/b6aects are separated by a distance R, the force betwb5n/5fxn, yq6ka4btheen them is F. If the distance between them is quadrupled, the force between them is

  03.18: Two identical electrical point charges Q, sepaxr5q ear,ax) kzq)9 s9rated by a distance produce an electrical force ofF on one another. If the distance is decreased to a distancr 5xzx),9)9qqsraa e ke of 0.40, what is the strength of
the resulting force?

  96.34: A point charge +q is placed midway between two poinjsv9q aj* ri//t charges +3q and -q separated by a distance 2d. If Coulomb’sv/a/q9r *isjj constant is k, the magnitude of the force on the charge +q is:

  01.31: A positive point charge of +q and a negative point charv)z w8b-ur8zxge of -q are separated by a distance d. What would be the magnitude of the electric field midway betweevuzrb-)8 xwz8 n the two charges?

  08.33: Two point charges are fixed on the x-axis inotherwise empty 9. u0e o2;jnxinbc1*d wbm(mospace as shown bel9.bmom(wcieb ox0 1nd;*2j n uow.
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-axindv0yiavs3-8i. ob 5 ,+ h*wjs,falct s in otherwise empty space as shown bel+-javs ntwb5v *.,8ifhs 3i0,dlyocaow.
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 ad-zzy*v8 0 if.8k0wo5cya l xgs shown in the accompanying diagram. At which of the labeled points is the fiel0k go dz-fylwca8xyz8i .5*v0d most nearly zero?

  98.30: Four positive point charges are arrec5igrhx5(o*w :/xymanged 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. The magnitude of the total force on charge 3 is h*wo x:c /y (mxe5igr5most nearly

  94.08: A point charge of +4.0 μC is placed on the negative x-axis 0./,x7dx en4 kmc4kwz69 ;y3mi9 tiaklz20 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 the origin. The net eleczndy/37z xx kk aim4k 9e4cw6, i9tml;tric field at the origin is zero. What is q?

  95.36: Assume the ele4; r.3zzaxkav ctric potential is zero at infinity. A point charge of +4.0μC is placed on the negativ4z kz;3vxr.a ae 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 omz7d.q/sp ug-n the corners of a 10 cm square as shown. What would be the direct-zsgu7 .pmd q/ion of the resulting electric
field at the center point P?

  14.10: Two charges −Q and +Q, are fkuvs b w5a(o)0ixed in place 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 direction of the electric field from the given c)sobka vuw 0(5harges?

  16.33 Given the configuration of three charges, +Q, +Q, axf( fmcid47/pnc xvh; 7 q0qm7va+7uund −2Q, which one of the following choices best represents the direction of the electric f+77n0vqxic 7 a f(muvx;q7hfpcu/m 4dield at the point P and the sign of the electric potential at P from these charges?

  17.43: A semi-circle has radius R, total charge Q, and0kov1zg)z l0x a charge per unit length g0 z xz)v0l1kgoiven 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?