95.26: Two positive point charges repel each other with force 0.36 N when j.x,/fpa5( h em5i3t zrvalt +their separation is 1.5 m. What force do they exert on eacfi x 3z+5a a/ ,pme(tlv5htj.rh other when their separation is 1.0 m?

  12.13 Approximately ho1e x4itb-ksip h/,a6zw many electrons must be removed from an electrically neutral object to give it e p/1hzi sa kx6i4,b-ta net charge of Q = + 1.00 C ?

  13.15 In a circuit, the flo 3)4 pyx/rcgpvw of electrons in a horizontal wire produces a constant current of 3.20 A for a time of 3 g )pc/yr4vx3p.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 identicalqy uo*j9ty;7q particles are fixed in place a distance of 0.50mapart. The electric force that one particle exerts on the other has a magnitude qyj7 9*y;u toqof 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 ratioz(ton v ,ke/fw9 5k.hbb0 ab*q of the gravitatio0 5wb*vf/o,k anh9(b be.qtkznal 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 o/r du5fp*szv51ga( ts f 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 pag1stzs/*u55d rfv(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 w9 -ji*c aw2v i.a ;;;tpfxajxfeight mg is attached 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 ofja xai;i;-f awx9;fpv2. jt*c 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 rxl h2 xlzw 87f+7p:fe mass M and charge Q is connected to an insulating massless string in a vacuum on Earth. A uniformrf zlwh82f:exl7+x7p 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 best indicates the trajectory of the mass?

  13.29 Two electrons enter a region between charged capacitor plates with equalsf:w f/-v ;0(ei .e(etvjxstr speed v. Electron A is directed horizontally to the left while electr .:r-/sxt(s0efe tv(fwj ;ive on 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 negativk, q+q d; 7llx/a,odh8rngjn/e 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 the positive point charge exerts on the negad ,+gh ;ann8o//lxk,dqjlqr7tive point charge?

  98.08: When two charged point-like ob/mv/nz. h 9hqpjects are separated by a distance R, the force between them is F. If the distance between them h/9/mh pv qzn.is quadrupled, the force between them is

  03.18: Two identical electr1 j3kkwhy xjs.8/+i(jx /mtwh ical point charges Q, separated by a distance produce an electrical forc/j kyx1xt8j w.hsk+h (jw/mi3 e ofF on one another. If 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 midway between two point charges +3q and rfn5 1jckd2 .e-q separated by a distance 2d. If Coulomb’s constant is k, the magnitude of the force on the cha c2.fn51kjer drge +q is:

  01.31: A positive point charge of +q i8yga g8,x22v(wjab + qcbx)d and a negative point charge of -q are separated by a distance d. What would be the m+8x y )b i v2jbc2wgxq8,(gaadagnitude of the electric field midway between the two charges?

  08.33: Two point charges are fixed on tps) nv36y2d6 epta jmdx,k/h* he x-axis inotherwise empty space as shown below pj3p6xa)de h,6s2vtd y nkm*/.
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 xb nzfw -,m.x*h:zwkk --axis in otherwise empty space as shown belowk*w,k: mz.-nbwz - hfx.
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 h5p.4d+ i(;tw 9y)iyvtm;p-qrb ep tbare arranged as shown in the accompanying diagram. At which of the labeled points is the field most nearly zer 59 twypm dip t. rbpt+bv4);(ihey-;qo?

  98.30: Four positive point charges are arrygujkg14.lxw 1i 57kwanged 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 5wki4x1 jug.k wl7yg51 .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 pc)drxu1 ,rm,;jp5vm,fqf l 2hlaced on the negative x-axis 0.20 m to the left of the origin, as shown in the accompanying figj2hv x f;r)m5l1,udp,cqr ,fmure. 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 ele-t tn lt5y-tar6gk76s1+gwf-tfkm p,ctric potential is zero at infinity. A point charge of +4.0μC is placed on the negative x-axis 0.20 m to the l,rktf t kgf-tg-1y -p75l6ts wmn a+t6eft 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 char fxa2ozpe b,9k9m3r (cges are arranged on the corners of a 10 cm square as shown. What would be the direction x29(pe,m3af9cor zbk 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, each a dist69jj,8lbng9ll+)lp vvgb -ms ance a from the origin as shown. At the point labeled P, a distavb9mlj p)b 6lvn 8,lg -9s+gjlnce along they-axis from the origin, what is the direction of the electric field from the given charges?

  16.33 Given the config*pj0baafyc24m+z b fpr:f* m;uration of three charges, +Q, +Q, and −2Q, which one of the following choices bezr+pyf f0*:f 4cmjb; ab pm*2ast 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 vhswt068j1o 9p ya(ny, total charge Q, and a charge per unit length given as p96n wha1 ovys08y(tj$λ=λ_0cosθ$ 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?