95.26: Two positive point charges repel each other with force4 hnzw-w3p)p; tds0 b6 .scwnd 0.36 N when their separation is 1.5 m. What force do they exert on 3n wdp0.wbwd;spnht4z)s6 c- each other when their separation is 1.0 m?

  12.13 Approximately how mseb 1d *bgeh 6a.u*p4/tu-wkcany electrons must be removed from an electrically neutral object to give it a net charge of Q = +6/tg-bu4d.* kaec pehs*buw 1 1.00 C ?

  13.15 In a circuit, the flow of electrons i nadckfn-x:7y+q x3 /sn a horizontal wire produces a constant current of 3.20 A for a time of 3.0 hour. Which one of the followx dy-an s +/:fq3xknc7ing 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 fv -b5cfobhi 14ixed in place a distance of 0.50mapart. The electric force that one particle exerts on the other has a magnitude of 3.00 N. Which one of t b1v4 bic5h-ofhe 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 ratio i 2m2jahdnu08of the gravitational force thmj nid 80hau22at 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 and mass M ra ;t:q;1xdlna g-x,hbeing placed near a helium nucleus (2 protons and 2 neutrons) of charge +2Q and mqn: t; dg-a,xxa;h1lr ass 4M. The objects 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 charg0+ 5tcvyzcsb4mcuz :,e 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 field E, as shown in the accompanying figure. In the presence of the field, the string makes a constant anglcms,:zct c+4uby5z0ve q with the vertical. What is the sign and magnitude of q?

  09.38: A small object of mass M and charge Q is connrpjo3mblby3/g9+3mcfk( fm6 ected 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 vertical as shown in the fi 3jbc plmg+3kform 9b y6f3(m/gure. When the string is cut, which of the illustrated paths best indicates the trajectory of the mass?

  13.29 Two electrons ent,cy9; i *wprcoer a region between charged capacitor plates with equal speed v. Electron A is directed horizontally to the left while electroi9yo c,* r;wcpn 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 ne oh0 e//j93tvf ymdn-kgative point charge placed a distance x away. If the distance be/h/ dfomtk- j9ne03 vytween 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-liamz) 378xind nke objects are separated by a distance R, the force betweenz7 mn3ix)8nad 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 distance produc ;c3lwn(jtc pxspg6 45,olg(pe an electrical force ofF on one another. If the distan; ( lc6(ogsltcnpx453pwjp,g ce is decreased to a distance of 0.40, what is the strength of
the resulting force?

  96.34: A point charge +q is placed s6; dtwwm0s6 7r0o timmidway between two point charges +3q and -q separated by a distance 2d. If Coulomb’s constant is k, the magnitude of the force on the charge +q is:wtd6mmi0 w6t0;o r 7ss

  01.31: A positive pob sw;b(8bdra* int charge of +q and a negative point charge of -q are separated by a distance d. What would be the magnitude of the electric field midway between trwb (a8b d*;bshe two charges?

  08.33: Two point charges are fixed on the x-axis inotherwise eml gwy8l1nq*3 kpty space as shown belol3gl8yn*w1 kq w.
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 otherwise empty space as sh reqi i*jc qd eg)y134w)vg65qownw4iydir)eq1v63ec5g jg ) *qq 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 show6u ip 1:tnq w6bv(0cxzn in the accompanying diagram. At w6 0xq61 pv :wibznctu(hich of the labeled points is the field most nearly zero?

  98.30: Four positive poinc sj*v0 16vgy/1/wwh ec.ncqxt 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 thc 0hg w16wx/e qccvvys./1n*je force between charges 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 is placed on the negative x-axis 0.20 m+s0li3 cr jm hgi7,2xs vtnd5)q1d (sm to the left of the origin, as shown in the accompanying figure. A second point charge q is placexgi15c7s d(q0v)+d2t3 s is lmhmj,rnd 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 at infinity. A point charge mb sdh;xyy9b qi.-(l2of +4.0μC is placed on the negative x-axis 0.20 m to the left of the origin, as shown in the accompanying figur bql 9-;y xyb(dshm.2ie. 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 ar u1gp6z;hm ze 7yj*c3 x:8zgtfranged on the corners of a 10 cm square as shown. What wouzu yht3z gm*pe:6jf 8;17 zxgcld be the direction of the resulting electric
field at the center point P?

  14.10: Two charges −Q and +Q, are fixed in place on the x-axi :imx tr5;oa zx)opi8lag.pkb dy;3z)(8 zl,y s, 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 direct: rm oag)z(lxi 3 x;azb.dylt8kio;,y85z)ppion of the electric field from the given charges?

  16.33 Given the configura/ xd q0igyfy;f26xr-dtion of three charges, +Q, +Q, and −2Q, which one of the following choices best represents the direction of the electric field at the point P and t dy;if-/ y xrf6d2qgx0he 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 unit lengfq5 fo ska;wjt4u w71+th gifk1w;fa45so7u +jt q wven 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?