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A certain capacitor can store 5.0 mC of charge when connected to a 2.0-V battery. What resistance is necessary to discharge it to 0.050 % of its initial charge in 0.80 min? Earth's magnetic field near the equator is roughly 0.050 mT northward. Determine the radius of the resulting path of a proton the instant it travels at 250 km/s in a direction of 55 degrees west of south. Also determine the pitch if the path is helical