Batteries are recharged by connecting them to a power supply (i.e., another battery) of greater emf in such a way that the current flows into the positive terminal of the battery being recharged, as was shown in Example 23.1. This reverse current through the battery replenishes its chemicals. The current is kept fairly low so as not to overheat the battery being recharged by dissipating energy in its internal resistance.
a. Suppose the real battery of Figure P23.55 is rechargeable. What emf power supply should be used for a 0.75 A recharging current?
b. If this power supply charges the battery for 10 minutes, how much energy goes into the battery? How much is dissipated as thermal energy in the internal resistance?
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