95.26: Two positive point charges repelu(,) uih; 91je sgfeiu each other with force 0.36 N when their separation is 1.5 m. What force do they exert on each otf(e ;)u,usj1ui hieg9her when their separation is 1.0 m?

  12.13 Approximately how many electrons must be removed from ande/ yvpvs+ t u+8)ova; electrically neutral object to give it a net charge of Q = +)vuo+8 pv;vsta+d/ey 1.00 C ?

  13.15 In a circuit, the flow of) susi7 4 m2wmr7a;qg 39cxzhx electrons in a horizontal wire produces a constant currenxz uma97 )2xrs;7g w4ichm sq3t 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 through a vertical cross-section of the wire during this time?

  13.07: Two identical particles are fixed in place a distance of;.du9 ,hl0::cn.cv3s eaiovzrm z0 i e 0.50mapart. The electric force that one particle exerts on the other has a z vo.i. curhs,ecvi;m 0:9de3a nz:0 lmagnitude of 3.00 N. Which one of the following choices best represents the magnitude of each particle’s charge?

  07.25: If two protons 0uze gfqy.mo *86p(fuare spaced by a distance R, what is the ratio of the graviqo*z. epmu(ugf8y6 f0tational 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 si5hcf8.l*y) ipyl +kexperiment 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 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 gravip.yky8f)is h5llc+*i ty.

  94.39: A small object with charge q and weight 8hqwjb.e he,7mg is attached to one end of a string of length L. The other end is attached to a stationary support. Twhj7hb, 8e.e qhe 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 thy6.;f dw0i xro an insulating mhdf.y 6rw;i 0xassless 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 region be)l5xcd nd k1ww3gl77zm*j* wetween charged capacitor plates with equal speed v. Electron A iel3m) ww5d*1 7k wxj zdg*cnl7s directed horizontally to the left while 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 iir0* s6b c2eaa 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 exerts on the nega sc6a 0iri*b2etive point charge?

  98.08: When two charged point-like objects are separated by a distance dl3g,b rsr +m2R, the force gslr2b+rdm3 ,between them is F. If the distance between them is quadrupled, the force between them is

  03.18: Two identical electrical point charges Q, 1;pk36 ygzryj separated by a distance produce an electrical force ofF on one another. If the distance is decreased to a distance of 0.40, what is the1pj6 ykz ;rgy3 strength of
the resulting force?

  96.34: A point charge +q is placr1+d0sqlfk7 +bkv if-ed midway 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 chaskdlkffvb +0-1ri q+7rge +q is:

  01.31: A positive point charge of +q and a negative point charge of -2g h(yg5hzqcsb.4e u8q are separated by a uz ygh c(b2sqg84 h5e.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-avsr: pj8ffn. *xis inotherwise empty space as shown bel:nf*jv 8rpfs.ow.
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 onzvj. l 8jv4xi2 the x-axis in otherwise empty space as shown ljz4x2. jv iv8below.
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 au *okqr.k2pu7ccompanying diagram. Atu2 .ukq*7orkp which of the labeled points is the field most nearly zero?

  98.30: Four positive point charges are arranged as shown in/ t0fhc*qkv9zr h j +cv77j;uu 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 charge 3 is most nea0v jc h* z7c uhvtf/9;u7jk+qrrly

  94.08: A point charge of +4.0 μC is placed on the negative x-axis 0.20gj n*cjixqh*r00r d 7i 1k:je2 m to the left of the origin, as shown in the accompanying figure. A second point charge q is placed on the positi i j:g*xrhek7 i0*jdcq1n r2j0ve 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 nqem vev(h;6 5jl*g( pzero at 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 at the o p vgj(h6e ne;m5lvq(*rigin is also zero. What is q’s charge?

  03.27: Four electrical charges are arranged on the corners of a 10 cm sqj/bw2e4p *uk iuare as shown. What would be the direction of the resul4/*kb2wie pju ting electric
field at the center point P?

  14.10: Two charges −Q and +Q, are fixed in place on the xh7vs/t* iik,+u kqw/r9v-.nsoy1cz m-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 the given charges? r iy ck9ust/ -kwms/qz7*.h,v n vi1+o

  16.33 Given the configuration of three charges, +Q, +Q, and −2Q,g5 ifm i sfu/0q2l2xu4 which one of the following choices best represents the direction of the electric field at the point P and the sign of the electric poten2/ sg4um2ixfif5l q 0utial at P from these charges?

  17.43: A semi-circle has radius R, total charge Q, and a charge per unit len b;bdr/u jyujz56bo71gth given yzj 6bdo/r bu 7j5b;1u 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?