95.26: Two positive point charges repel each other with force 0.36 N when thei,r6 ; bd,a uvywit5h;yr separation is 1.5 m. What force do they exert on each other when their separation iay6v d w,uht,5;rb ;yis 1.0 m?

  12.13 Approximately how many electrons must be removed fro)pkc9:zujl ou/0s +g:o:s up0d3 a wexm an electrically neutral object to give itpss l poauc0/d3 u::xjo9w0:k+ zg)eu a net charge of Q = + 1.00 C ?

  13.15 In a circuit, the flow of electrons in a horizontal wire pr4 i6w8 c3kq.pilb)kcnqa tk+6oduces 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 throughpl btq 6waikc+.kc)3i 6 4qn8k a vertical cross-section of the wire during this time?

  13.07: Two identical particles are fixed in place a distance of 0gt, c9k:nedpy / lw*l-.50mapart. The electric 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 ch9 /elwgt ,n kcp-l:*ydarge?

  07.25: If two protons are spa5f 0ghea o7)la(tsxpa nn7 2.pced by a distance R, what is the ratio of the gravita fp5s7 pla oh0 xnaet()7a.n2gtional 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 chu ex(pi6r) g1gaj fx-.arge Q and mass M being placed near a helium nucleus (2 protons and eg fg1j)xxr6ai.-u(p 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 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 attachehmna;a3:0d -u(z s ghkd 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 fied;3(a g:nh0u hk- asmzld, 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 7/d hz.wk3x do 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 vertical as shown in the figure. When the strzko d7/hw.dx 3ing is cut, which of the illustrated paths best indicates the trajectory of the mass?

  13.29 Two electrons enter a region between charged capacitor plat t uyq-1,y93xztrgd 2yes with equal speed v. Electron A is directed horizontally to the left while electron B is direzqdyt u-y21t9,3ygx r cted 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 (-:i 4 y 6fn5-lrmgg uarf*8f/afab)muvp nq ,F on a negative point charge placed a distance x away. If the distance between the two point charges is halvfa8nfag mq)u -gu r6(f:fayp,*54n-im/lrvb ed, 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 objects are separatedwu pb./e 4:gbd by a distance R, the force between them is F. If 4u.dgbweb: p/the distance between them is quadrupled, the force between them is

  03.18: Two identical electrical point charges Q, separated suo g8wp g ey.q25hy09by a distance produce an electrical force ofF on one another. If the distanh. 29sgypy80 wqguo e5ce is decreased to a distance of 0.40, what is the strength of
the resulting force?

  96.34: A point charge +q is plalrkh*(;t5u8ilno te-ljo9j85 f1 wmxy e.v) vced midway between two point charges +3q and -q separated by a dist 1uw-klljt.;f)9m v* o hl5re8 5eiotj(vnxy8ance 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 tox.1zo7qosg (-p :pjpoint charge of -q are separated by a distance d. What would be the magnitude of the1 -oxpg(o:stopzq . 7j electric field midway between the two charges?

  08.33: Two point charges are fixed on the x-axis inotherwise .om v.)wz;0r 2weqsfw empty space as shown below;rmsv.fe)20zoq w w.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 chaw gfw1q -;owzd6fon4/ rges are fixed on the x-axis in otherwise empty space as shown below.zwodw1 q64g; -/n owff
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 arrang)x1,tkj qfpa)ed as shown in the accompanying diagram. At which of the labeled points tjf1)axk, )pq is the field most nearly zero?

  98.30: Four positive point charges are arranged as shown in th91/t + mcfxrqn/5mf e4uov2f le accompanying diagram. The force between charges 1 and 3 is 6.0 N; the force between chalo9 2fnec f f/v51t+qu r4mmx/rges 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 charge 3 is most nearly

  94.08: A point charge of +4.0 μC is placed on the negative x-axisptnz0 lh2nau1g;oasrg 1z8 +0 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 lga2a;hg11800u nnoz+ sz prtat the origin is zero. What is q?

  95.36: Assume the electric potential is zero at infinixb3k. ewf k)e8ty. 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 eb3fw) k.e8 xk0.30 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 /jsmbsp zo ;-9the corners of a 10 cm square as shown. What would be the direction of the rm9pz/b o;ss-jesulting electric
field at the center point P?

  14.10: Two charges −Q and +Q, are fixed in place on the x-axisfsj w+.pb5 2iy3 qt5tn, each a distance a from the origin as shown. At the pin+byws 5tj3 tp f52.qoint 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 configuration of three charges, +Q, +Q, and −2Q, whin k:l5n 9at1jvch one of the following choices best represents the direction of the electric field at the point P a9vl:1njnt 5k and the sign of the electric potential at P from these charges?

  17.43: A semi-circle h(v ..wt6n r cnto anj4v2e9p(pas radius R, total charge Q, and a charge per unit length gipwj v(v( 9 conpr..4en6t2ntaven 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?