subject
Physics, 02.08.2019 17:10 babygirl1015jm

It is commonly recommended that hot foods be cooled first to room temperature by simply waiting a while before they are put into the refrigerator to save energy. despite this commonsense recommendation, a person keeps cooking a large pan of stew three times a week and putting the pan into the refrigerator while it is still hot, thinking that the money saved is probably too little. but he says he can be convinced if you can show that the money saved is significant. the average mass of the pan and its contents is 5 kg. the average temperature of the kitchen is 23°c, and the average temperature of the food is 95˚c when it is taken off the stove. the refrigerated space is maintained at 3˚c, and the average specific heat of the food and the pan can be taken to be 3.9 kj/kg ˚c. if the refrigerator has a coefficient of performance of 1.5 and the cost of electricity is 10 cents per kwh, determine how much this person will save a year by waiting for the food to cool to room temperature before putting it into the refrigerator.

ansver
Answers: 1

Another question on Physics

question
Physics, 21.06.2019 19:30
Contrast the force of gravity between these pairs of objects a 1 kg mass and a 2 kg mass that are 1 m apart and two 2 kg masses that are 1 m apart
Answers: 2
question
Physics, 22.06.2019 02:30
Mass (kg) force (n) 5 25 10 50 15 75 20 100 a student was trying to find the relationship between mass and force. he placed four different masses on a table and pulled them using a spring scale. the table shows the different masses used in the experiment and the force required to pull each mass. the student concluded that more force was required to pull heavier objects. what comment would you make regarding his conclusion? a) no clear relation can be observed between mass and force from the data. b) there is a direct proportion between the mass and force listed in the table. c) gravity should have been taken into account while performing the experiment. d) there is an inverse proportion between the mass and force listed in the table.
Answers: 2
question
Physics, 22.06.2019 09:30
In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j? 1. write the equation 2.list out your known variables 3.plug the numbers into the equations 4.solve 5.write your solution statement that includes initial energy and final
Answers: 3
question
Physics, 22.06.2019 21:30
Global climatic patterns are changing because of the melting of polar ice caps. the melting of polar ice caps is an example of the interaction between the atmosphere and cryosphere cryosphere and geosphere hydrosphere and geosphere biosphere and cryosphere
Answers: 1
You know the right answer?
It is commonly recommended that hot foods be cooled first to room temperature by simply waiting a wh...
Questions
question
English, 14.01.2021 22:10
question
Mathematics, 14.01.2021 22:10
question
Mathematics, 14.01.2021 22:10
question
Mathematics, 14.01.2021 22:10
Questions on the website: 13722363