95.26: Two positive point charges repel each other wiij un1o (rrp;:mt0bkll g; g3vh*- ;munc ls/0th force 0.36 N when their separation is 1.5 m. What force do they exert ongo0mpl /;v- ir u;0r(bj1 :gl3n*;kutnhmc ls each other when their separation is 1.0 m?

  12.13 Approximately how many electrons must be removed from an elbdw7p 6odven5fid 1:o10n6nf kh.+yv ectrically neutral object townb1ifen 5vdo6d k+1h67vd0p f o:yn. give it a net charge of Q = + 1.00 C ?

  13.15 In a circuit, the flow okfsqc.;qs,l,k, - w9d)m ;u/ c 5mya0bzr qleof electrons in a horizontal 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 verticalq/eqq w )duz ;y.lfm,mc, ;s59s rkal0- bcok, cross-section of the wire during this time?

  13.07: Two identical particles are fixed in place a distance of 0v) z.jz*4nw2f s7pxgn m0zru8k 5zht 8.50mapart. The electric force that one particle exert .wut *k2 zzx8f5 0v4 ng7p8rm)zszhnjs 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 ratih2fs 4p 9pqh3u(fnm0xo of the gravitational force that one sx(nf 4hfuh23 m90p qp
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 setsgyj+w3rz qk 4, up an 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 view, which choice best describes the ob,krgw3j4 z+qyject 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 c;tr 0) jx;vlgoi +(+qj-q8ssb3ahyc charge q and weight 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 f3- ( st s)v8boy+jc +q;jrqiagl0cx h;ield 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 +e o:rwsm0gd 5and charge Q is connected to an insulating massless string in a vacuum on Earth. A uniform electric fiel mo+5:ew 0gsrdd 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 plpc8 vy 6biq5+uates with equal speed v. Electron A is directed cp5i+b6qy8v u 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 magnitudew4e5x6md ,fqhu5rf,d syy*j; t-rv- x F on a negative point charge placed a distan6v,y4sq duffr-,* yxxm5- retwd 5;jhce 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 negative point charge?

  98.08: When two charged point-like objen *ya 2e((gyfpcts are separated by a distance R, the force betwee2f*yyn ag((pen them is F. If the distance between them is quadrupled, the force between them is

  03.18: Two identical electrical point charges Q, separated by a divgvl eyh 2z,dfj:i3 (i5u((zfstance produce an electrical force ofF on one another. If the distance is decreased to a distance of 0.udfz2,ihl 3((v jv fizg:e5(y40, what is the strength of
the resulting force?

  96.34: A point charge +q is placed midway between two point chargesfhczntc/+za1 ky7ly79 h3 y a/ +3q and -q separated by a distanc3917tfcl+aa yn/hy 7h y zkz/ce 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 nega 2hff;cbrwnj/ 3ar*a( tive point charge of -q are separated by a distance d. What would be the magnitude of the electric field midwah/a n2jrfac3;r *f(b wy between the two charges?

  08.33: Two point charges ar6z tq47 qxc:7riv g0jxe fixed on the x-axis inotherwise empty space as shown beloi7607zvq x 4ctxqjr:gw.
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 chargwpjq(r p r 5)zx;1r2lres are fixed on the x-axis in otherwise empty space as sho5;wrpj)2rp q1lr( xr zwn 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/eb1 z-oqh3a, rynwgkz 3*(9 qleyd 7n diagram. At which of the labar ky93nodn1 /z,ghq7e*w q-3 z b(yeleled points is the field most nearly zero?

  98.30: Four positive poi hd6 g.o(3 l:nyi btrxot,xg9+nt charges are 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 tonl39xr bgdt o.,h+( x:yg6tiotal force on charge 3 is most nearly

  94.08: A point charge ofgploh1k. p8,a +4.0 μC 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 pg,h.1o8a pkl 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 potk dacu 9:bxo 1npl1o0-ential is zero at infinity. A point charge of +4.0μC is placed on the neg9nx 1ac0d1:ol-b uokp 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 charges are arranged on the corners of a 10 cm squ o7ng q32w2iqdare as shown. What wgo i3q7dn 2q2would be the direction of the resulting electric
field at the center point P?

  14.10: Two charges −Q 3vcrb 9gqz8 -aand +Q, are fixed in place on the x-axis, each a distance a froc3za -qb gvr89m 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 charges?

  16.33 Given the configurzg hcom/ --/z:xlbk;hation of three charges, +Q, +Q, and −2Q, which one of the following choices best represents the direction of tz-g -mkl;/ xcozhb:h/he 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, and a chart gt 2u 30wtziz,wv*c+qg8yw:ge per unit length given,q0 8wt: w v2*w3tzucgytz ig+ 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?