8B Worksheet Answers 6. Current, Resistance, Ohm’s Law 1. a) The two flow rates must be the same (otherwise more water enters the junction than leaves, resulting in a buildup of water with no place to put it!) b) The currents through A, B, C, D, and E must all be the same: If current A were bigger than current B, say, then more charge enters the region between A and B than leaves. Charge is conserved, and can’t leave the wire, so we must be getting a buildup of charge between A and B. But, we’re in a steady state, and the currents are constant, so no such charge buildup can occur. c) Since the current before and after the resistor is the same, it wouldn’t make sense to say that current gets ‘used up’. 2. a) The water particles gain more energy from the pump on Waterfall 1. The energy they gain is gravitational potential energy - Waterfall 1 has a larger drop in height than Waterfall 2, so it takes more energy to bring water molecules from the bottom of the Waterfall to the top. b) Waterwheel 1 again has energy (in the form of rotational kinetic energy). This
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