Chapter 7: Homework 2

Chapter 7: Homework 2 Question 5 of 10 Current Attempt in Progress You put 1.08 liter ( 1.08 kg) of room-temperature (200C) water ( = 4190 J/kg/K ) into an electric pot that is turned on and transfers heat to the water. Using a beater. you actively stir the water. doing work on the water. You observe that after 4 minutes, the water starts to boil (temperature IOOOC). From the manufacturer. you know that the electric pot uses 1200 W. Define the system to be the water. Part I During this 4 minutes, what is the change in thermal energy of the water? Chapter 7: Homework 2 Question 6 of 10 View Policies Current Attempt in Progress Part I -/10 (a) If you follow a diet of 1900 food calories per day (1900 kilocalories), what is your average power consumption in watts? (A food or "large" calorie is a unit of energy equal to 4.2 x 103 J; a regular or "small" calorie is equal to 4.2 J.) Note for comparison that the power consumption in a table lamp is typically about Save for Later Part 2 Attempts: O of 4 used Submit Answer 100 watts. Save for Later part 2 watts Attempts: O of 4 used Submit Answer During this 4 minutes. what is the energy transferred to the system due to a temperature difference? Save for Later Part 3 Attempts: O Of 4 used Submit Answer (b) How many days of a diet of 1900 large calories are equivalent to the gravitational energy change from sea level to the top of Mount Everest, 8848 m above sea level? Assume your mass is 72 kg. (The body is not anywhere near 100% efficient in converting chemical energy into change in altitude. Also note that this is Starting from a fundamental principle, calculate the work done by the beater in stirring the water. in addition to your basal metabolism.) days eTextbook and Media Save for Later Attempts: O of 4 used eTextbook and Media Save for Later Submit Answer SUPPORT Attem ts: O of 4 used SUPPORT Submit Answer