Calculating Cost of Operating Lamp

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To calculate the daily cost of operating a lamp drawing 1.90 A from a 110 V line, the formula used is current multiplied by voltage, cost per kWh, and hours in a day. The initial calculation resulted in $0.310992, but this was identified as incorrect. The correct approach requires rounding to the nearest tenth, leading to a suggested answer of $0.30. The importance of precision in the final answer is emphasized, as the problem specifically requests it to the nearest dime. Accurate calculations are essential for determining energy costs effectively.
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Homework Statement


Compute the cost per day of operating a lamp that draws a current of 1.90 A from a 110 V line. Assume the cost of energy from the power company is $0.0620 / kWh. NOTE: Enter your response with tenths precision.


The Attempt at a Solution


1.90*110V*.0620*24 = .310992
but this answer is wrong
 
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GlobalDuty said:

Homework Statement


Compute the cost per day of operating a lamp that draws a current of 1.90 A from a 110 V line. Assume the cost of energy from the power company is $0.0620 / kWh. NOTE: Enter your response with tenths precision.


The Attempt at a Solution


1.90*110V*.0620*24 = .310992
but this answer is wrong
you did divide by 1000 W/kW, but the problem asks for the answer to the nearest tenth (nearest dime).
 
yeah i divided by 1000 at the end, but .3 is wrong
 
GlobalDuty said:
yeah i divided by 1000 at the end, but .3 is wrong

Try $0.30
 

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