Q1. Three equal point charges, each with a charge of 1.90 mu C, are placed at the corners of an equilateral triangle whose sides have the length of 0.470 m. What is the potential energy of the system?
Q2. A solid, rectangular iron bar measures .40cm by 1.0cm by 30cm. Find the resistance between each of the three pairs of opposing faces, assume the faces in question are quipotentials.
Q3. A freight train has a mass of 1.7 × 10^7 kg. If the locomotive can exert a constant pull of 6.6 × 10^5 N, how long does it take to increase the speed of train from rest to 87 km/h?