95.26: Two positive point charges repel each other with force 0.36 N when t*q)ue uk4puz62m.ho2 bmd/r b7 s,ua sheir separation is 1.5 m. What force do they exert on each other when thekeazbhm726o.d2 /uurups * mu)b,4qsir separation is 1.0 m?

  12.13 Approximately how many elect tq ubqbu-b*p(9a*i;pw1j2vxrons must be removed from an electrically neutral object to give it a bujw 291(p babv -txu*iq*;pq net charge of Q = + 1.00 C ?

  13.15 In a circuit, the flow of electrons in a horiyhl.um+ 7i7tizontal wire produces a constant current of 3.20 A for a time of 3.0 hour. Which one of the fo yl7thi7m+. iullowing 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. ja:zck3 pro,rl* 1f4q50mapart. The electric force that one particle exerts on the oth orj3f,kl 41zp arc:q*er 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 spaceda f6vxet82hd 4t84mkh by a distance R, what is the ratio of the gravitational force that 2 tm6a88d4 h hkxt4vefone
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 wiypv;d4xl -xpu (8q7lzth 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 choidv;7x8p zxllyu(4 p-qce 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 isr) j30r,dscdab b ;b1x attached to one end of a string of length L. The other end is attached to a statio0 jb,drb ;sa)cb31xrd nary 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 e7edbab j*r, 0 Q is connected to an insulating b0 ,bae d*je7rmassless 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 trajectory of the mass?

  13.29 Two electrons enter a regiobg(4 ev,z 15j 6ym m8sn)wtztin between charged capacitor plates with equal speed v. Electron A is directed horizontally to the left whiltz4gwjmt158 e,b y(iv6 nszm )e 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 magnitude F on a negaud8x g2jt;fo0) m-lkj tive 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 negative pt-jmfod8u;2j g 0l x)koint charge?

  98.08: When two charged point-like objects are separaz 4+fj;; dr(j duk )sna m3-h(xnr9atfted by a distance R, the force between them is F. If the distance betw9nfu k (4dh rt jn;d+z()a;amrj3xf-seen them is quadrupled, the force between them is

  03.18: Two identical electrical point charges Q, nd*qsm)93)pwlap 9t q separated by a distance produce an electrical force ofF on one another. If the dlm p ps d*)q99qnt3wa)istance is decreased to a distance of 0.40, what is the strength of
the resulting force?

  96.34: A point charge +q is placed midwa-nwn me )e9pb6y between two point charges +3q and -q separated by a wnnm6p-9b) eedistance 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 point 16hkd97h8yedsmx.qfcharge of -q are separatedh8e kqs 9yfx6d .7hm1d by a distance d. 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 inotherwisef:u5m;2 d/ngdr d)+: kyzmtsq empty space as shown +:/sddt2 5kq) fmn zy m:u;grdbelow.
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 inbq+ l l/8xzyo6;pslp9o) ome8 otherwise empty space as shown below. )pybl6 oel/m8 l+zoqsox8p;9
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 iod/l(g7wxau o2,bo w( n the accompanying diagram. At which of the labeled points is thbu w(l( oadg27oo/, xwe field most nearly zero?

  98.30: Four positive point charges are arranged as-a: i69dkf yor 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 chaf i:9d roy6ka-rges 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 ismo/hx4 ,ctfc0p y -)7 lj5obyn 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 mto the right of the origin. The net electric field at 0 jxo -hytc5omb ,p4)n/f7ycl the origin is zero. What is q?

  95.36: Assume the electric potential is zero at infinity. A po: hi*vyd(nzi*int charge of +4.0μC is placed on the negative x-axis 0.20 m t iv*yh(di* n:zo 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 corner po;8 bplfl+y0s of a 10 cm square as shown. What would be the direction of the resulti0bp;yof +llp8 ng electric
field at the center point P?

  14.10: Two charges −Q and j/z-0w.bp uf0 vj0yb)u*ahvf tg,yt0 +Q, are fixed in place on the x-axis, each a distance a from the origin as shown. At the point labeled P, a diybfj ab0u 0 j/0.z hv,0yvutwtg )-f*pstance 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 charges, +Q, +Q, and −2Q, which one of thyg5w3 vh(al 4ae following choices best represents the direction of the electric field at the point P and the sign of the electric potential at P from these ch4 y (awghal53varges?

  17.43: A semi-circle has rprs s(g1gliw c u,5i, ,vlm9z)adius R, total charge Q, and a charge per unit length givslrgcvsw( l1u ,z9 ipi)gm,5,en 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?