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P 2.5-6 Figure P 2.5-6 shows a battery connected to a load. The load in Figure P 2.5-6 might represent automobile headlights, a digital camera, or a cell phone. The energy supplied by the battery to load is given by When the battery voltage is constant and the load resistance is fixed, then the battery current will be constant and |
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The capacity of a battery is the product of the battery current and time required to discharge the battery. Consequently, the energy stored in a battery is equal to the product of the battery voltage and the battery capacity. The capacity is usually given with the units of Ampere-hours (Ah). A new 12-V battery having a capacity of 800 mAh is connected to a load that draws a current of 25 mA. (a) How long will it take for the load to discharge the battery? (b) How much energy will be supplied to the load during the time required to discharge the battery? |
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Figure
P 2.5-6 |
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(a) How long will it take for the load to
discharge the battery? |
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Solving for discharge time |
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(b) How much energy will be supplied to the
load during the time required to discharge the battery? |
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