95.26: Two positive point charges repel each other with foj+qepmo1ky *ve4 f 5 v;f87uxtrce 0.36 N when their separation is 1.5 m. What force do they exert on each other when their separation is 1.0 mmq81fv+5eke j pou7vyfx 4*t ;?

  12.13 Approximately how man, g3 b*o9m 2ul1 jbkts6;4g mhvxu c9uaz8m,jdy electrons must be removed from an electrically neutral object to gijz ka3gjg 48vmm6cb, htd ul2;o91m usubx,9*ve it a net charge of Q = + 1.00 C ?

  13.15 In a circuit, the flow of electrons in a horizontal wire jou h;yok lgt7(2v:;h produces a constant current of 3.20 A for a time ofy;goh:t 2;(v ljou7k h 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 0.50map /p3j :mqta4oox vzstf ym+u a3f7+p9mit++u(art. The electric force that one particle exerts on the othe9 fmujayzm+a+++(qi p3u: s ofo4mt px 7/tvt3r 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 iz d)3gzk(ik8are spaced by a distance R, what is the ratio of the gravitational force that ozik3k8dgiz( )ne
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 andjby 5+amus/3b 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 experien5 msja3/ b+buyces 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 weight mg is 57ydb 6rxudiu2al)1t 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.l )ixu51 adtrud2b7y6 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 objx,px55te8nl a/bs+l aect of mass M and charge Q is connected to an insulating massless string in a vacuum on Earth. A uniform electric field exists throughout the regiltn/5ap,e bx8+ asl5 xon 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 betw) joy,q h1d8sheen charged capacitor plates with equal speeyj,oqhhd s )18d v. 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 for:lh+ lovw)2ezpu2 fv+ ce of 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 magnite+lpovh)f22wuz+lv: ude 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 +okmjufy pz5p2 qsxud s9.7h*6 f44spforce between them is F. If the distance betw ppshfzy5o4+ u9*.mpd ux26fk4s jq7seen them is quadrupled, the force between them is

  03.18: Two identical electrical point charges Q, separated by a c 0ayvky13e4odistance produce an electrical force ofF on one another. If the distance is decreased to a distance of 0.40, ca4k3 ey ov1y0what is the strength of
the resulting force?

  96.34: A point charge +e 7vmf4 p(meg1)qp-sdvxw+q+q is placed midway between two point charges +3q and -q separated by a distance 2d. If Coulombwd v vp+ xseqm7()-+4mp1qf ge’s constant is k, the magnitude of the force on the charge +q is:

  01.31: A positive point charge of +q and a negative poibmv;bf sr 8a;1;7c xz -8lbauint charge of -q are separated by a distance d. What would be the magnilxi -z1b ra8 fbm7s;a;b8cv;utude of the electric field midway between the two charges?

  08.33: Two point charges are fixed on the x-axis inotherwise empty sph1otj.:cg5t bd4 reaf +z.ts6ace as shown be r4a szj1et g6o..5chdt+f:btlow.
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 otherwisbfk/t wy85p9f 5.ibpy e empty space as shopi55/fbp 9yw8 fb ky.twn 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 t/dz lb(2+ vxlvhe accompanying diagram. At which of the labeled points is the (vlb /v+2zd lxfield most nearly zero?

  98.30: Four positive point charges are arrand5o- +g tfoh a,jou:qs.,;lenged as shown in the accompanying diagram. The force between charges 1 and 3 is 6.0dute,lh- o+jg;osn :o.,fa5q 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 most nearly

  94.08: A point charge of +4.0 μC is placed on the negativr7u .i ) uu ,(lif9qb1acbsbr/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 mto the right of the or7. lsai()u19rubfbq , i/b curigin. The net electric field at the origin is zero. What is q?

  95.36: Assume the electric potential is zero at infinity. A point chargeknhoxv590 .ahbk/c: u 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 point charge q is placed on the positive x-axis 0.30 m to the right of the origin. The net electric potuhxk5 0kacb. 9/ ohv:nential at the origin is also zero. What is q’s charge?

  03.27: Four electrical charges are arran 7 ttigsl2c7i1tx6rj )ged on the corners of a 10 cm square as shown. What would be the direction of the resur7si tjtitxc1 7l 62g)lting electric
field at the center point P?

  14.10: Two charges −Q and +Q, are fixed in place o ky8 u5is))7piu3jem fn the x-axis, each a distance a from the origin as shown. At the point labeled P, a distance along they-axis from the ore )yiu3 )8ujspikmf 57igin, what is the direction of the electric field from the given charges?

  16.33 Given the configuration of three charges, +Q, +Q, and −2Q, fsiv:14m,rfqdom u (i(x*)ob which one of the following choices best represents the direction of the electric field at the point P and the sign of the electric potentia 4ris iv o(d)oum,fxb1mq*f (:l at P from these charges?

  17.43: A semi-circle has radius R, total charge Q, az6hvb*wr;crzxgd5 6yp , ,+ dmnd a charge per unit length r,,d5 hrdx6* m;p 6b+wzgcvzy 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?