A 0.253-kg coffee mug is made from a material that has a specific heat capacity of 944 J/kg C° and contains 0.277 kg of water. The cup and water are at 20.6 °C. To make a cup of coffee, a small electric heater is immersed in the water and brings it to a boil in two minutes. Assume that the cup and water always have the same temperature and determine the minimum power rating of this heater. Number i Units <>

A 0.253-kg coffee mug is made from a material that has a specific heat capacity of 944 J/kg C° and contains 0.277 kg of water. The cup and water are at 20.6 °C. To make a cup of coffee, a small electric heater is immersed in the water and brings it to a boil in two minutes. Assume that the cup and water always have the same temperature and determine the minimum power rating of this heater. Number i Units <>

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

See similar textbooks

Similar questions

A heat engine running backward is called a refrigerator if its purpose is to extract heat from a cold reservoir. The same engine running backward is called a heat pump if its purpose is to exhaust warm air into the hot reservoir. Heat pumps are widely used for home heating. You can think of a heat pump as a refrigerator that is cooling the already cold outdoors and, with its exhaust heat QH, warming the indoors. Perhaps this seems a little silly, but consider the following. Electricity can be directly used to heat a home by passing an electric current through a heating coil. This is a direct, 100% conversion of work to heat. That is, 19.0 kW of electric power (generated by doing work at the rate 19.0 kJ/s at the power plant) produces heat energy inside the home at a rate of 19.0 kJ/s. Suppose that the neighbor's home has a heat pump with a coefficient of performance of 3.00, a realistic value. NOTE: With a refrigerator, "what you get" is heat removed. But with a heat pump, "what you…
A small metal cube with a thermal mass mc and an initial temperature 0 is dropped into a container of water that is actively maintained at a constant temperature 0w. The cube quickly comes to rest on the bottom surface of the container. The bottom surface is maintained at a constant temperature 0 (note that this is different from 0w). The thermal resistance between the cube and the water is Rcw while the thermal resistance between the bottom surface of the container and the cube is RCB. The temperature of the cube is denoted by 0c. a) Draw the system schematic indicating the assumed directions of the heat transfer rates. Label all the nodes and system parameters. b) Derive the governing equation for the temperature of the cube, 0c. c) Where does to appear in the system schematic and how does it affect the governing equations? d) Calculate the steady-state temperature of the cube, css, assuming the following system parameters: 0o = 21°C, 0B = 6°C, 0w = 0°C, Rcw = 2°C/W, and RCB = 4°C/W
Consider the process shown in (Figure 1). Figure p (kPa) 400- EV 200- 100 200 300 0₁ 0 V (cm³) 1 of 1 How much work is done on the gas in this process? Express your answer with the appropriate units. W = Submit μA Value Provide Feedback Request Answer Units ?
em 5 A NATO base in northern Norway is warmed with a heat pump that uses 7.0°C ocean water as the cold reservoir, Heat extracted from the ocean water warms fluid to 80° C; this warmed fluid is used to heat the building When the system is working at full capacity, 2000 kW of heat are delivered to the building at the cost of 600 kW of electric energy. Part A What is the actual coefficient of performance of the system? COP Submit Request Answer Part B What is the theoretical maximum coefficient of performance of the system? COPX Submit Request Answar P Type here to search
Question 10. A detective has been called to the scene of a crime where a dead body has just been discovered. The detective arrives at 9:00 AM and begins to investigate. Immediately, the temperature of the body is taken and is found to be 90.3°F. The detective checks the programmable thermostat and finds that the room has been kept at a constant 68.0°F for the past 3 days. After the evidence from the crime scene is collected, the temperature of the body is taken once more and found to be 89.0°F. This last temperature reading was taken exactly one hour after the first one. The following day, the detective is asked "At what time did our victim die?" Assuming that the victim's body temperature was normal (98.6°F) prior to death, what should the detective answer?
cna you help with part C?
Liquid helium has a very low boiling point, 4.2 K, as well as a very low latent heat of vaporization, 2.00 104 J/kg. If energy is transferred to a container of liquid helium at the boiling point from an immersed electric heater at a rate of 19.0 W, how long does it take to boil away 2.30 kg of the liquid? _________________min
Question 5 Specific Heat of Solid Substances Substance D Aluminum B silver; because it is a transition metal with the lowest specific heat value C Iron Copper Tin Given the specific heat information presented, which substance would make the BEST material to create a pan for cooking and why? D Specific Heat (J/kg°C) 899 443 385 213 Tin - because it has a low specific heat, which means it conducts heat the best. Aluminum - because it has a high specific heat, which means it conducts heat the best. Copper - because it has a mid-level specific heat, which means it is a good insulator. Iron - because it has a mid-level specific heat, which means it is a good conductor.
You design an engine that takes in 1.50x104 J of heat at 650 K in each cycle and rejects heat at a temperature of 290 K. The engine completes 240 cycles in 1 minute. What is the theoretical maximum power output of your engine, in horsepower? 1 Watt = 1 Joule/s = 0.00134102 horsepower 44.5 hp 15.0 hp 6.50 hp 2.90 hp
A Carnot heat engine operates between thermal reservoirs at Th and Tc. What is the theoretical efficiency, η, of this engine? Part (a) Write an expression for thermal efficiency, η. Part (b) Solve numerically for the thermal efficiency, η, assuming that Th = 910°C and Tc = 310°C.
I have got variations in answers when I have asked this question. I have got answers anywhere from 75000 J, 6079.5 J to 74919 J and -6.221kJ. I need to know the correct answer for this I am hopelessly confused.