95.26: Two positive point charges repel each other wit ),vqvw2 v3nbirw+md5h force 0.36 N when their separation is 1.5 m. What force do they exert on each o)q3+nv rwvd,b 2 wm5vither when their separation is 1.0 m?

  12.13 Approximately how many electrons must be removed from an electricb49d)s)u7lt v32 - oucq ymnchally neutral ob27oct- u3yvmc)n)sq9dbl h4u ject to give it a net charge of Q = + 1.00 C ?

  13.15 In a circuit, the flow of electrons in ce3+eu0yky9v+(m yiy o7 bcc+3t ).xfdfgb 3ia horizontal wire produces a constant current of 3.20cbvxk.7 f9 c e3ft+ 0+m( yyicdo)y+3yebigu3 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 during this time?

  13.07: Two identical particles are fixed in place a dist0+slu* syo3nzbm7/ ) + taemz :h drs/8bm1wnhance of 0.50mapart. The electric force that one particle exerts on the other has a magnitude of 3.00 N. Which one of the following choic zbran 3b7sthm1yom n0/)lude s8hw+msz: */+es best represents the magnitude of each particle’s charge?

  07.25: If two protons are spaced by a distance op65er(n hdkm)5po:fws2 o(mR, what is the ratio of the gravitation wdr)5 f5n(pook m6esh:op2( mal 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 an experiment with a proton of charge Q andc gzt-deppx itfr**z)xg7 ( )( 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,*zg-ri z gd f7)*cpx) xt((ept 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 a7r0dble:,i i grul )vavj5y(pj,20 pqnd 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 field E, as shown in the accompanying figure. In the presence of the field, the string makes a constant angle q withi,d rp:qil ajl v2,5)eyrjp b00(v7ug the vertical. What is the sign and magnitude of q?

  09.38: A small object of masyo 2,xu3v 5xbms M and charge Q is connected to 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 vertica 3yub,m52 xovxl 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 regionvn18ry0utx l *, pwale2;qdcb*2o ;jz between charged capacitor plates with equal speed v. Electron A is directed horizontally to the left while electron B is y* qzpoul2x20jbaw ev1dr;t;8,ln *cdirected 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 ofi,vx5q ( vw+ o je42*sey5hcva 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 magnitude of the new force that the positive point charge oqes2 cwxaev4,+v j5*viy(5 hexerts on the negative point charge?

  98.08: When two charged point-like objects are jx;mn v2*xp. dseparated by a distance R, the force ; n jp.v*md2xxbetween them is F. If the distance between them is quadrupled, the force between them is

  03.18: Two identicalft;wu).uw- e c electrical point charges Q, separated by a distance produce an electrical force ofF on one au -u; wt.fecw)nother. 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 two point c1*jl-exo ( ujh6z,co vu(7o ifharges +3q and -q separated by a distance 2d. If Coulomb’s constant is k, the magnitude of the force on the charge +q iuu6i,oo7h (1zvlco- j xj( *fes:

  01.31: A positive point charge of +q and a negative point charge of -q are sepu4 sk:i3rp;6pnf(u: r bavim0arated by a distan;sr4u:ar p3kb (u6 nimvf 0i:pce d. What would be the magnitude of the electric field midway between the two charges?

  08.33: Two point charges ab2)hccn;oio8 .)y+gcdk5g yq c ( xi*ure fixed on the x-axis inotherwise empty space as shown belowk52gx;)(cdc b*ncy 8)iuh . ocgio+qy .
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 otherwo 40fpz)kay :j7ctf3mise empty space as shown below.3ytofa p7 j)m0: kcfz4
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 accompan)xlm6 1:nwze6kwpox ; ying diagram. At which of txxz w ):6;okle6n1pmwhe labeled points is the field most nearly zero?

  98.30: Four positive point chpgs o ,f q-5dc z s4uvri((66rmbsm0l)arges 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 total force on cham06)m6rfs q d rz((p gl4-si5svb, ucorge 3 is most nearly

  94.08: A point charge of +4.0 μC is placed on the negative x-axis 0.20 m to thekq xa( *mwh bb4-g1d1 (+h-i*bnaeavo left of the origin, as shown in thehob((wi n a*h qkm+-4-a*1de 1gbxavb 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 q?

  95.36: Assume the electric potent biz 2or3nz76eial is zero at infinity. A point charge of +4.0μC is placed on the negative x-axis 0.20n2e36ziz7o br 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 squ6o6gva:7 zzyx,n1 6 ddufa8uxare as shown. What would be the direction of the ,d8zaxx6f7 :a6o uuyz16 dvgn resulting electric
field at the center point P?

  14.10: Two charges −Q and +Q, are fixed in place on the x/d cc+te6fwqxx h1 *7f-axis, each 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 t1et7d6w*/fcqxf x c+hhe given charges?

  16.33 Given the configuration of three charges, +Q, +Q, and −2Q, 0wz zq4hf u)d/zpbdhl : omy)*k:w)s(which one of the following choices best represents the direction of the electric field at the point P and the sign of the el: kz:w)/ o*hmd4lh(zz ps0yd f)wbqu)ectric potential at P from these charges?

  17.43: A semi-circle has radius R, total charge Q, and a cjeohc ml8.*cfo 0qk/+ 0bo)xaharge per unit length xh.*0b8ok cjco 0 l/f+m oqa)egiven 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?