Electrical Energy and Power (Wrong because of decimal place)

AI Thread Summary
The discussion centers on a homework problem calculating the cost of watching a 21-hour World Series on a 180-W television. The user incorrectly converted the power from watts to kilowatts, resulting in an inflated cost of $264,600 instead of the expected 26 cents. The error stems from multiplying 180 W by 10^3 instead of dividing by 1,000 to convert to kilowatts. Clarification on unit conversion is emphasized as crucial for accurate calculations. Properly converting 180 W to 0.18 kW will yield the correct cost.
AznBoi
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Homework Statement


How much does it cost to watch a complete 21-hour-long World Series on a 180-W television set? Assume that electricity costs $0.070/kWh

The Attempt at a Solution



\frac {0.070}{kWh} = \frac {x}{(180*10^{3}kW)(21h)}

\frac {0.070*(180*10^3 kW)(21h)}{kWh} = x

I got $264,600 when the answer is suppose to be 26 cents. What am I doing wrong here? Thanks.
 
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Why do you have 180*10^3kW?
 
Yes, you've converted your power the wrong way.
 

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