Calculating Charge in a 9V, 12W Radio

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SUMMARY

The discussion focuses on calculating the charge passing through a 9V, 12W radio over a duration of 1.33 hours. The initial calculations incorrectly applied Ohm's Law and the power formula, leading to an erroneous current value of 40A. The correct approach involves using the formula Q = I × t, where the current I is derived from the power and voltage. The final correct charge calculation is 6.384 x 10^4 coulombs.

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A person runs a 9.0 V, 12.0 W radio for 1.33 hours. How many coulombs of charge pass through the wires in the radio during this time?

I used Power= pot difference/Resistance = 9v/120w=7.5e-2

I=current
Then I used I²=P/R= 120v/7.5e-2 = 1.6e3
I=40A

1.33h*60mins*60secs = 4.788e3

Q=Charge
Then Q=It = (40A)(4.788e3 secs) = 1.92e5 but this is not the right answer.

Any help would be great. Thanks!
 
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I made a mistake with the first equations it is P=pot diff²/R => R= pot diff²/R so I ended up recalculating and I got 6.384x10^4 but it is still not right.
 
Never mind I figured out
 

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