A circuit is constructed from two batteries and two wires, as shown in the diagram below. Battery 1 Battery 2 Each battery has an emf of 1.7 volts. Each wire is 28 cm long, and has a diameter of 0.0007 meters. The wires are made of a metal which has 7e+28 mobile electrons per cubic meter; the electron mobility is 5e-05 (m/s)/(V/m). A steady current runs through the circuit. The locations marked by "x" and labeled by a letter are in the interior of the wire. Which of these statements about the electric field in the interior of the wires, at the locations marked by "x"s, are true? Check all that apply. At every marked location the magnitude of the electric field is the same. At location D the electric field points to the right. The magnitude of the electric field at location G is larger than the magnitude of the electric field at location F. Which of the following equations is a correct energy conservation (round-trip potential difference) equation for this circuit, along a round trip path starting at the negative end of battery #1 and traveling counterclockwise through the circuit (that is, traveling to the left through the battery, and continuing on around the circuit in the same direction)? O +1.7 V - 1.7 V = 0 O -1.7 V + E*(0.28 m) = 0 O -1.7 V + E*(0.28 m) - 1.7 V + E*(0.28 m) = 0 D +1.7 V - E*(0.28 m) = 0 O -1.7 V + E*(0.28 m) + 1.7 V - E*(0.28 m) = 0 +1.7V - E*(0.28 m) + 1.7V - E*(0.28 m) = 0 O +1.7 V - E*(0.28 m) - 1.7 V + E*(0.28 m) = 0 What is the magnitude of the electric field at location B? EB = V/m How many electrons per second enter the positive end of battery #2? electrons/s If the cross-sectional area of both wires were increased by a factor of 2, what would the be magnitude of the electric field at location B? new value of EB = V/m Which of the diagrams below best shows the approximate distribution of excess charge on the surface of the circuit? C V V (a) (b) [c) (d) Additional Materials