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peaceandlove
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Homework Statement
A steam iron draws 5.3 A from a 114 V line. (a) How much internal energy is produced in 76 minutes? Answer in J. (b) How much does it cost at $0.75/kW*hr to run the steam iron for 76 minutes? Answer in units of cents.
Homework Equations
1) U = VIt
The Attempt at a Solution
Using equation 1, I found the internal energy produced to be 2755152 J. However, I'm having a problem with figuring out part (b). I know I'm supposed to convert J to kW*hr in order to figure out the cost and that 1 watt = 1 J/s. Using that information I divided the internal energy by the time, 4560 seconds, giving me 604.2 watts or 0.6042 kW. I then times that by the cost per kW/hr and the amount of time in hours. I got 0.57399, but for some reason it's not the right answer.