95.26: Two positive point charges repel each other with force 0.36 N when iphygvf)i e.l69h 3 j(their separ. i 9(gh)vfj6lyeh3ipation is 1.5 m. What force do they exert on each other when their separation is 1.0 m?

  12.13 Approximately how many electrons must be re ieztq(8i-:m.wsk ;b hmoved from an electrically neutral object to give it hb-k(8t:iimswqz; .ea net charge of Q = + 1.00 C ?

  13.15 In a circuit, the flow of electrons in a horizontal wire produces a con/0+wdrudrr 7t u6loh ;f5w)cp stant 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 duriwddu;+rth5 lu0rwo7 /fc r)p6ng this time?

  13.07: Two identical particles are fixed in place a distance ofu xqa7+swim,6t-l 4ls 0.50mapart. The electric force that one particle exerts on the other has a magnitude of 3.00 qtwml 6 i 47s,uals+-xN. Which one of the following choices best represents the magnitude of each particle’s charge?

  07.25: If two protons are spaced ja4c n3n5ybc;by a distance R, what is the ratio of the gravitationyc b3n5;jacn4 al 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 a9tz ax/r /xs+g5,ua xln 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 asx5+ x/ aglt ,urx/9zto 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 ;* ig2 it54tkhpkck*x with charge q and weight mg is attached to one end of a string of length L. The otherk;kti 5*ipt c2h4gx*k 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 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 connected toz +fb0hl yva,3 an insulating massless string in a vacuum on Earth. A uniform electric field exists throua0bly z v,h3+fghout 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 betweeql7sfbvr8:81o m tesgx0x91u n charged capacitor plates with equal speed v. Elecb0v8u:gmtes8o1x1 lq fr xs97 tron 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 force of magnihuke6y7e 89antude F on a negative point charge placed a distance x away. If the distance between the two point charg9 ehuyn87ea6k es 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 objects are separated by a pnm ;p,8pimgu8c,k0 hdistance R, the force between them is F. If the dista, km08uhipcmg;n ,p8p nce between them is quadrupled, the force between them is

  03.18: Two identical electrical point charges Q, separated by a distance prod+x:j nvrh3f8sd 3n c(cuce an electrical force ofF+: 83xncr3n v fsjhd(c 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 tw,7mp*o7tgk kyo point charges +3q and -q separated by a distanc 77y*p ,okmkgte 2d. If Coulomb’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 poink2xq pjq- . - od;sgrg;d.1wtxt charge of -q are separated by a distance d;x qk-d;g gjw-p1 toqsx. 2dr.. What would be the magnitude of the electric field midway between the two charges?

  08.33: Two point charges are fixed on the x-axis iq5ecci i9*ig :/r izbf l6t94enotherwise empty space as shown belet 6izi iqlicfc/e 4gb 5:9r9*ow.
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 3o 050v1l cy( ceouo3 /rbdfksin otherwise empty space as shown belowu5( s3kdbr 3fc0 y le/v01ooco.
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 , n( tcc f/ao5yrv27lodiagram. At which of the labeno2lcr tcf (5,7vy/oaled points is the field most nearly zero?

  98.30: Four positive point charges areo6of1s 0e4g zpd/ b8mg arranged 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 38g sg10e fb 6dm/p4ozo is most nearly

  94.08: A point charge of +4.0 μC is placed on the negative x-absyo (ar ),+k.szdjm1xis 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 origin. The net electric field at the origin is zero. What is qma ,)jzkdso.y1 +b (rs?

  95.36: Assume the electric potenti)k jv2vj3 jo qq1pjr*wl0,i.zal is zero at infinity. A point charge of +4.0μC is placed on the negative x-axis 0.20 m to the left of the origin, as shown i o0jr pq*vl.2j)3vjwkzq ,j1in 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 on the corners of a 10 cm s4o/u )gqi 6sluquare as shown. What would be the directio uqol g4)6s/iun 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, ; -46p-- wlvvaagr xtmr49d ckeach a distance a from the origin as shown. a9x 6wamgpd -;c vk4-t 4r-lvrAt 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 chargessqzr6y:.lpul6 a w q13, +Q, +Q, and −2Q, which one of the following choices best represents the direction of the electric field at the point P an.zs61 al63yp :qurl qwd the sign of the electric potential at P from these charges?

  17.43: A semi-circle has radius R, total charge Q, and a charge per l0q/ c 7zftuh8unit length uzqf0/h87 clt 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?