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nobrainer612
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Homework Statement
An ideal 9V battery is connected to a resistive divider consisting of a 330 Ohm and a 600Ohm resistor. A 1.5V rechargeable battery in series with a 1.5k Ohm resistor is connected in parallel with the 330 Ohm resistor. The battery has a capacity of 1200mAh and is half charged. How much charge does it hold after 10 hours?
Homework Equations
V=R*i
battery charging time = capacity of the battery / charging current power output of the charger:
hr = mAh / mA
AAA – AA – C – D sizes rechargeable batteries:
hours ( charging time ) equals to 12 x Ahr OR 12/100 x mAh ( 12/100 x mAh = hrs )
Power = V*i
The Attempt at a Solution
I tried to find the current going to the 1.5k Ohm dc source. I first combined the R1 and Ri2(internal) as parallel.
1/Req = 1/330 + 1/1500
Req= 270.5
Then I combined R1 to Req since they are in series:
270.5 + 600 = 870.5 Ohm
The the total Req is 870.5 Ohm
Then I tried to find the current passing through the total Req:
V=Ri
i=9V/870.5
i=0.01033
Then I will use the equation:
battery charging time = capacity of the battery / charging current power output of the charger:
= 1200mAH/0.01033
= 116166 .. wow
At this point I am totally confused. Since this is such a large number, I feel like I am doing it wrong.
Any help is appreciated.