Posted by admin | Posted in Uncategorized | Posted on 15-12-2009
Tags: diy, electronics, flashlight, flashlight battery corrosion, flashlight battery disposal, flashlight battery life, flashlight battery sizes, flashlight battery tester, led, shopping
PLEASE help find energy stored in a 54Ah 13V car battery and 1.2Ah 1.4 V flashlight battery!!?
Car batteries are often rated in amp-hours. This rating indicates the quantity of charge that can pass through the battery before the battery’s chemical energy must be restored by the car’s generator or some other source. The amp-hour unit is convenient for simple calculations. For example, a 60-amp-hour battery can supply a current of 1.0 A for 60 h (or 60 A for 1.0 h) before going dead. Find the energy stored in the following.
(a) a 54 A-h, 13 V car battery
(b) a 1.2 A-h, 1.4 V flashlight battery
Ive gotten it wrong on every attempt so far. For a I initially got 702 and b i got 1.7… I cant figure out what im doing wrong.. the unit for both answers in Joules
a) E = Vit = 13*54 = 702 = 0.702 kwh
b) E = Vit = 1.4*1.2 = 1.68 = 0.00168 kwh
Solar charging a 6 volt flashlight battery
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