95.26: Two positive point charges repel each other withhg9tr)ciz dhfy7/v-af7, w f- force 0.36 N when their separation is 1.5 m. What force do they exer 7--dig z)f9h7ty f cvhrwaf,/t on each other when their separation is 1.0 m?

  12.13 Approximately how many electrons must be - l 8eg7u+ifoxku7p: *p*6*s itrkp lmremoved from an electrically neutral object to give it a net charge of s-lk87 : kte ip up**pigml7x*o 6ufr+Q = + 1.00 C ?

  13.15 In a circuit, the flow of electrons in a horizontal wire producesu r8-0uki9y+bb h+o oo 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 pouyorb0h 9kbu +o-i8+ ass through a vertical cross-section of the wire during this time?

  13.07: Two identical part0zrpoi-xd5ic 1 n5o9v icles are fixed in place a distance of 0.50mapart. The e n1dropi5o 5- xzc09ivlectric 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 spacedq)u. o-xw 0zx0vch7yn(u,bz,e nbwb* by a distance R, what is the ratio of the gravitational force that onecw y,zbz 7n)e -u,bw0bxuo*vh qx .0(n
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 experimuiv1gtuf*6)8tfo,bef ne 3 qhu2vq ; .ent 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 objeci.v*ogv)tf uuqe ,;q2eft f6b1nh u8 3ts 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 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 attached to on + 1s3yw8js m0fp5szwt i6eww7e end of a string of length L. The oth3tp6s7 y0m51sfwe ws wi8wz j+er 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 9(r fj3kr1j8swtwl*qto 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 shown in the figure. When the string is cut, which of the illustrated paths best indicates the tra1k8 r*r9(wtwqjsjf3ljectory of the mass?

  13.29 Two electrons enter a region between zuzn(s35r iyo.*loy *charged capacitor plates with equal speed v. Electron A is directed horizontally to the left while electron suz3ryy( *oz iol. n5*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 magnieq,//ly3 nnultude 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 n/ l,y3/uqlnude 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,a+5qx*3hn kpawk :m,t the force between them is w q:hatxp53a*mn,k+ kF. If the distance between them is quadrupled, the force between them is

  03.18: Two identical electrical point charges Q, separated by a distaoh7.mv u2s bz48zunc. nce produce an electrical force ofF on onecbuh78zm zn 4v .ou2.s 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 mijxhz. -*a4evr(ienod-; 7ioz2l :fr d dway between two point charges +3q and -q separated by a distance 2d. If Coulomb’s constantvi-fr;:*o ld 7je-zr 4nozi(x2 h.ade is k, the magnitude of the force on the charge +q is:

  01.31: A positive point chargemj1w 25-ue,ctp x 5owe of +q and a negative point charge of -q are separated by a distance d. What would be the magnitude of the electric field e,tc-52 upx5j ew mwo1midway between the two charges?

  08.33: Two point charges are fixed on t pf:7yog2u 9lphe x-axis inotherwise empty space as shown bey:g927l fopu plow.
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 7itsv*a:;tum sp*r3 p in otherwise empty space as showu*v 3mt; irt sp*s:7apn 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 +*9i atbmo(a; b-njg)vQ and –4Q are arranged as shown in the accompanying diagram. At which;ab ()o tmbg9 a*-vinj of the labeled points is the field most nearly zero?

  98.30: Four positive point charges are arranged as shown in /sf7soin47fbx0wvk6 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 andfis67s/xw40 n 7kof bv 4 is 3.0 N. The magnitude of the total force on charge 3 is most nearly

  94.08: A point charge of di+( gi;yw,(lam)kvg v( y ru-0d(ils+4.0 μC is placed on the negative x-axis 0.20 m to the left of the origin, as shown in the ;)rw,y v(( 0yl-dg(k ivs(liiad+mugaccompanying 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 potential is zero ,hksi *d+ q-rq 9v, o8kcqmzb9at 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 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 q,br,kqm+k hi8 o9- vs*cqd9zat the origin is also zero. What is q’s charge?

  03.27: Four electrical charges are arranged on the corners of a 1d j7 b c9+uvna5us+xv30 cm square as shown. What would be the direction of the resulti+7u x+vunsa 5b9cvjd3ng electric
field at the center point P?

  14.10: Two charges −Q and +Q, are fixed in place on the x-axis, each- + gyg+ds :dirywbc2-khk2ru8q xu 3 qs7:ko3 a distance a from 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 y:-i ogd 2r+sqb u3hk7s:8c+wugrkyx2 q3-dkgiven charges?

  16.33 Given the configuration of three cki :y 42 )vwdndkr8)ubharges, +Q, +Q, and −2Q, which one of the following choices best represents the direction of rv wnkd: )2)8ib dy4kuthe 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, /3 /i,dse mtirand a charge per unit lengt3tim, // srdeih 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?