Problem 3: (II) Three positive particles of equal charge, +17.0 μC, are located at the corners of an equilateral triangle of side 15.0 cm (Fig. 16-53). Calculate the magnitude and direction of the net force on each particle due to the other two. FIGURE 16-53 +17.0 μC 15.0 cm 15.0 cm Problem 12. +17.0 με 15.0 cm +17.0 μС

60 O In Fig. 21-43, six charged particles surround particle 7 at ra dial distances of either d = 1.0 cm or 2d, as drawn. The charges are q1 = +2e,92 = +4e, q3 = +e,q4= +4e,q5 = +2e,q6 = +8e,q7 = +6e with e = 1.60 x 10-19C. What is the magnitude of the net electro static force on particle 7? Figure 21-43 Problem 60. 4.

83 In Fig. 24-66, point P is at distance di = 4.00 m from particle 1 (q = -2e) 41 and distance dz = 2.00 m from particle ida 2 (42 = +2e), with both particles fixed in place. (a) With V = 0 at infinity, what is V at P? If we bring a particle of charge q3 = +2e from infinity to P. Figure 24-66 Problem 83. (b) how much work do we do and (c) what is the potential energy of the three-particle system?

(a) Calculate the strength and direction of the electric field, E, due to point charge of 2.5 nC at a distance 4 mm from the charge. For the direction, consider the line joining the point charge and point at the distance 4 mm. The direction on this line away from the charge is positive and the direction towards the charge is negative.

(13) Particles 1 and 2 have the same magnitude of charge but opposite in -q2 = 7.36 nC. However, mı > m2 sign: q1 14.9 µg such that particle 1 can be regarded as stationary in their electrical interaction. Suppose that they are initially separated by a distance of 1.71 cm. The magnitude of the escape velocity of particle 2 needed to escape from the pull of particle 1 to infinity is most nearly (A) 87.5 m/s. (B) 61.9 m/s. (C) 75.8 m/s. (D) 43.7 m/s. (E) 30.9 m/s.

Two small charged spheres hang from cords of equal length l as shown in Fig. 16–64 and make small angles 01 and 02 with the vertical. (a) If Q1 = Q, Q2 = 2Q, and m1 = m2 = m, determine the ratio 01/02. (b) Estimate the distance between the spheres. FIGURE 16–64 Problem 52. Q1 Q2

Figure 16-50 shows electric field lines due to a point charge. What can you say about the field at point 1 compared with the field at point 2? (a) The field at point 2 is larger, because point 2 is on a field line. (b) The field at point 1 is larger, because point 1 is not on a field line. (c) The field at point 1 is zero, because point 1 is not on a field line. (d) The field at point 1 is larger, because the field lines are closer together in that region. $2 FIGURE 16–50 MisConceptual Question 4.

(c) An electric dipole consists of 0.003 kg spheres charged to ∓3e-09 C at the ends of a 0.16 m long non-conducting rod of mass 0.006 kg (don't try to look up "electric dipole", it won’t help you. For the sake of this problem, it is just a fancy word for what I just described). The dipole rotates on a frictionless pivot at its center. The dipole is held perpendicular to a uniform electric field with a field strength 1000 V/m, then released. i.What is the dipole's angular velocity (in rad/s) at the instant it is aligned with the electric field? (HINT: Look up the moment of inertia of the rotating rod about its center and don't forget the rotational kinetic energy term (along with the other terms) when you set up your conservation of energy problem). a)0.0534 b)0.446 c)0.289 d)0.119 e)0.137 f)0.205 (d) Four 1.9e-08 C charges are held in location to form a perfect square with sides of length 0.1 m. Two of the charges from opposing corners are released simultaneously, the other two are…

Figure 22-40 shows an electric dipole. What are the (a) magni- tude and (b) direction (rèlative to the positive direction of the x axis) of the dipole's electric field at point P, located at distance r> d? +q d/2 d/2 Fig. 22-40 Problem 19.