95.26: Two positive point charges repel each other wi,qu09w(g/w9 ubw0m ctytcr+ k th force 0.36 N when their separation is 1.5 m. What force do they exert on each other whc/u 0rq u+m9 t b9,ww0(gytcwken their separation is 1.0 m?

  12.13 Approximately how many electrons must be removed from an;5yjkx0g90nctd f z6m electrically neutr jy5c90 zxtgkf0m dn6;al object to give it a net charge of Q = + 1.00 C ?

  13.15 In a circuit, the flow of electrons in a horizontal wire producudkmwlvj(e5 /o )vfz1* wb6p0nc 7rn2 es a constant current of j 5v uo2 /)n6c(r0mw p17fekvld*b nzw3.20 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 are fixed in place a distance of 0.50mapart. Thfa( ocu+qt)c) e elot+) caf)(uq cectric force that one particle exerts on the other has a magnitude of 3.00 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 thezz-1r/r / gl, w7c k(bxszva*t gravitational 7r*lksz ac1z- /bt g(w,v zxr/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 experiment with a proton n/ 7rq+ . 2wclfjfvp5fft:r3 mof 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 view, which choice best describes the object that experiences the greatest mag5 j tfrrp/nlf27cvq:f3mw f+.nitude 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 h6 - flha6cii7attached 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 horizontahhc6l 67fii -al 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 conn 8w:nzgcybn3i(ys0cm j.b :hff19j b5ected 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 show:i3(n8b. n :yyjms 19hwzjc 0fgfcb5bn 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 a region between charged capacitor p / j3k2gd yd,3xlj)gavlates with equal speed vvjja /dgkd ,gxy 32)l3. Electron A is directed 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 fo19)whic bwgm. rce of magnitude F on a negative point charge placed a distance x away. If the distance between the two point charges is halvbwch91img.w ) ed, 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 fo/-6adiq(b clyj j lax7x +l6v6rce between them is F. If the distance between them is qua7ac aq-ilv6ldj6xl 6 y+ /xjb(drupled, the force between them is

  03.18: Two identical electrical point charges Q, separated by a distance produ3j;d.d-w)h e-hl2vraoilj ka3 46v txce an electrical force ofF on one another. If o3wkx);-d .dallr4e6av vj ti2h-3 hj the distance is decreased to a distance of 0.40, what is the strength of
the resulting force?

  96.34: A point charge +q is placed midejcozwsqvs.gt8z;h.njh. -n,.0 u y9 way between two point charges +3q and -q separated by a distance 2d. If Coulomb’s constant is k, the magnitud9 swqsznu.ch,.get . yojvj n0h-z8 ;.e of the force on the charge +q is:

  01.31: A positive point charge of +q and a negative point charge of (n+ltsvi1t1hxjp 73rp. )xe zm h +dp6-q are separated by a distance d. Whaitr7pxvext +pj m)h+ sh1.z 3dl1n6(pt would be the magnitude of the electric field midway between the two charges?

  08.33: Two point charges are fixed on the x-axis inotherwise emplqgk 26 0jik9rty space as shown 2k6q90 kglrji 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-axis in otherwise e*0fawy 8wy*3nds 0 ouwmpty space as show ud*ya8f 0*w 0ow3snywn 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 di2 ycfsc59v o2bagram. At which of the labeled poib29cvoy2c s5 fnts is the field most nearly zero?

  98.30: Four positive point charges are arranged as shown in the accompanying 93oz cy -;1nvtzabki9diagram. The force between charges 1 and 3 is 6.0 N; the force b;-tbz a cv3kz9ny1o9ietween 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 placed8+ ltcrlw6:f lkkt b(3 on the negative x-axis 0.20 m to the left of the origin, as shown in(l:k lc+l8k3f6btwt r 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 pop. f 3h:* -zio )yrz8f+htvlcztential is zero at infinity. A point charge of +4.0μC is placed on the neg8c)fo z:t3- hv.pry zihz+l*f ative 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 cha :fm9t ynz(d-rrges are arranged on the corners of a 10 cm square as shown. What would be the direction of the resulting elect(9t- yf n:dzrmric
field at the center point P?

  14.10: Two charges −Q and +Q, are fixed in place on the x-axis, eafpxr/-bnbe.r rq 3;i2ch a distance a from the origin as shxbr2 b .rf/re-q;in3 pown. 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 c*p lq*c l2/1d5d t/fhlm)nii / ll)f,bhfvhm6harges, +Q, +Q, and −2Q, which one of th i fil)56 1 ll)vdhhcq*dnlfm/f hm*/,bpl2t /e following 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 radius R, total charge Q,to oz 3y7yv,h2c14gwa and a charge per unit length gi473th y oaozgyw,cv12 ven 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?