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Marina1234567
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Homework Statement
A battery has an EMF of 12.0 volts and internal resistance of 3 ohms
A 21.0 ohm resistance is connected to the battery.
0.5 Amps flow through the battery, hence 0.5 Amps flows through the 21.0 ohm resistor
The potential difference across the 21 ohm resistor is 10.5 Volts, hence the terminal voltage of the battery is 10.5 Volts.
The question is How much work does the battery connected to the 21.0 ohm resisitor perform in one minute?
Homework Equations
Voltage = Joule/coloumb
1 amp = coloumb/ second = (6.258 *10^18 electrons) second
1 electron has a charge -1.60*10^-19 coloumbs
The Attempt at a Solution
current = 0.5 Amps = 3.125*10^18 electron/ second = 30 coloumbs pass wire per minute
usisng the definition of EMF (voltage): 30 coloumbs/ minute * 10.5 volts = 315 Joules
however it keeps on telling me that answer is wrong i know its simple i just can't see it right now thanx