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(a) If an isolated conducting sphere 5.7 cm in radius has a net charge of 4.3 JC and if V = 0 at infinity, what is the potential on the surface of the sphere? (b) Can this situation actually occur, given that the air around the sphere undergoes electrical breakdown when the field exceeds 3.0 MV/m?Two metal spheres, each of radius 4.2 cm, have a center-to-center separation of 2.5 m. Sphere 1 has a charge of +1.1 x 10'8 C; sphere 2 has a charge of -2.6 x 10'8 C. Assume that the separation is large enough for us to assume that the charge on each sphere is uniformly distributed (the spheres do not affect each other). With V = O at innity, calculate in volts (a) the potential at the point halfway between their centers and the potential on the surface of (b) sphere 1 and (c) sphere 2. In the figure point P is at a distance d1 = 4.39 m from particle 1 (q1 = -3e) and distance d2 = 1.35 m from particle 2 (q2 = +3e), with both particles fixed in place. (a) With V =0 at infinity, what is V at P? If we bring a particle of charge 93 = +3e from infinity to P, (b) how much work do we do and (c) what is the potential energy of the three-particle system? O 41Electric removal of COVID-19 drops. Sneezing, coughing, singing, talking, and even breathing can release water drops with COVID-19 that can transmit the virus from an infected person to someone else. The drops are charged. So, one way to filter the air in a room where this transmission might occur is to send the air and drops through an electric field where the field can remove the charged drops. Assume a drop has radius r = 2.32 um and charge (-2.86 x 104)e and it travels through a rectangular pipe of length L = 9.10 cm and height h = 9.20 cm, as shown in a side view in the figure below. The sides are insulators, and the top and bottom are charged plates with a potential difference of AV. The drop enters the pipe with a horizontal velocity of magnitude v = 8.40 cm/s. What AV is needed if the drop enters the pipe near the low-potential plate but is collected by the high-potential plate at the far end of the pipe? - High-potential plate Air flow Low- potential plate