Problem 14.04 A person consumes about 2900 Cal a day. 1 Cal = 4186 J, and 1 kWh
ID: 1419526 • Letter: P
Question
Problem 14.04 A person consumes about 2900 Cal a day. 1 Cal = 4186 J, and 1 kWh = 860 Cal. Part A What is this energy in joules? Express your answer using two significant figures. Q = m J SubmitMy AnswersGive Up Part B What is this energy in kilowatt-hours? Express your answer using two significant figures. Q = m kWh SubmitMy AnswersGive Up Part C If a power company charges about 14 ¢ per kilowatt-hour, how much would this energy cost per day if the person bought it from the power company? Express your answer using two significant figures. Cost = m $ per day SubmitMy AnswersGive Up Provide FeedbackContinue
Explanation / Answer
a) 2900 kCal = 2900x4186 Joules = 12139400 Joule = 1.2x107 Joule
b) 860 kCal = 1kWh
2900 kCal = 3.37 kWh
c) Cost = 3.37x14 = 47.2 ¢