Refrigerator Definition and 148 Threads

The interior lighting of the refrigerators is provided by incandescent lamps whose switches are actuated by the opening of the refrigerator door. Consider a refrigerator whose 30-W lightbulb remains on continuously as a result of a malfunction of the switch. If the refrigerator has a COP of...

please explain me..

hi everyone I am doing a project on thermoelectric Refrigerator and from my research i found out about a p-type material known as Zn4Sb3 which has a high figure of merit however, as far as i know to make a thermoelectric module, it has to be combined with an n-tpye material. is it that any...

Homework Statement A mover loads a 186kg refrigerator into a moving van by pushing it up a 10.0m friction free ramp at an angle of inclination of 11.0degrees. How much work is done by the mover thats all that was given.Homework Equations w=(F)(d)...work is =force times displacement The Attempt...

Homework Statement A refrigerator is operated by a 0.25 hp (1 hp=746 watts) motor. If the interior is to be maintained at 2.00 degrees Celsius and the room temperature of the room is 35 degrees C, what is the maximum heat leak in watts that can be tolerated? Assume that the coefficient of...

Can you please help me with this question?? about a refrigerator and heat? Homework Statement A) Where does the heat go which is given off by the condensation coils of the refrigerator in your kitchen? B) Its 90 degrees in your kitchen, you decide all windows and all doors so no heat...

Homework Statement A refrigerator is rated at 370 W. What is the maximum amount of heat it can absorb from the food compartment in 1 minute if the food compartment temperature is 0 deg C and it releases heat into a room at 20 degrees C. Homework Equations COP=Qc/W W=Qh-Qc The...

Homework Statement A restaurant refrigerator has a coefficient of performance of 4.5. If the temperature in the kitchen outside the refrigerator is 28^\circ C, what is the lowest temperature that could be obtained inside the refrigerator if it were ideal?Homework Equations According to...

I'm having a little trouble in completing this problem. I would appreciate your answer if anyone knows how to solve it. Thanks An ideal refrigerator removes heat at a rate of 0.15kW from an interior temperature of 1 degree celsius. The exhaust from the refrigerator is 45 degrees celsius. How...

Homework Statement A refrigerator is approximately a uniform parallelepiped h = 8 ft tall, w = 3 ft wide, and d = 2 ft deep. It sits upright on a truck with its 3 ft dimension in the direction of travel. Assume that the refrigerator cannot slide on the truck and that its mass is 130 kg. For...

Hi, I think I have confused myself over the COP of a refrigerator. I have refrigeration system and a certain set of values which enable me to plot a P-s diagram. The refrigerant is R-12. I also have another set of 4 results for varying evaporator pressures, and I have drawn all these...

I know the formulas for efficiencies e of heat pump (it is e<=Tmax/(Tmax-Tmin)) and refrigerator (e<=Tmin/(Tmax-Tmin)), where Tmax and Tmin are temperatures of warmer and colder (respectively) involved containers. These formulas make me puzzled, as efficiencies seem to be possibly bigger than 1...

Homework Statement 1 L of 20 degree C water is placed in a refrigerator. The refrigerator's motor must supply an extra 8 W to chill the water to 5 degrees C in 1 hr. What is the refrigerator's coefficient of performance? Homework Equations The Attempt at a Solution 8W = 8 J/s...

Hi Everyone! I have couple of questions this time! :D 1) In refrigerator we say that we have to do some work on system to flow heat from lower temp body to higher temp reservoir , so if temp1 > temp2 then temp2 + work = temp1 now what i want to ask is that what kind of work we do on...

Homework Statement If you leave the refrigerator door open in an enclosed room, will it cool the room over time or no? Homework Equations The Attempt at a Solution I am thinking of the warm air/cool aire situation in my way of answering this problem. Any advice as to what the...

Homework Statement A mover's dolly is used to deliver a refrigerator up a ramp into a house. The refrigerator has a mass of 110 kg. The ramp is 2.1 m long and rises 0.42 m. THe mover pulls the dolly with constant velocity and with a steady force of 445 N up the ramp. The dolly and ramp...

Homework Statement A refrigerator is marked 80W and 250 V. What is likely to happen if the voltage falls to 50V? Homework Equations P=V^2/R V=IR The Attempt at a Solution --------------------------------------------------------- R=V^2/P =250*250/80 =781.25 ohm Assuming the...

Heat does not naturally flow from a cool body to a hot body. A refrigerator, however, does remove heat from the icebox and expels it as warm air to the outside world. In terms of enery, what is required to make this process function?

Homework Statement Air conditioners operate on the same principle as refrigerators. Consider an air conditioner that has 7.00 kg of refrigerant flowing through its circuit each cycle. The refrigerant enters the evaporator coils in phase equilibrium, with 54.0 % of its mass as liquid and the...

MODS close this thread down i figured out the answer myselfHomework Statement A refrigerator has a coefficient of performance of 2.16. Each cycle it absorbs an amount of heat equal to 3.435×104 J from the cold reservoir. i need to find a) the mechanical energy required each cycle to operate...

I have a flat rectangular refrigerator magnet. I was curious to where the N S poles were, so I took a standard bar magnet to it to find them. Curiously, the bar magnet does not seem to be repelled at any place of the refrig magnet. Where would the poles be on a flat, bendable refrig magnet?

What do you recommend for a water filter that either fits on one's faucet or utilizes a pitcher?

The inside of an ideal refrigerator is at a temperature , while the heating coils on the back of the refrigerator are at a temperature . Owing to a malfunctioning switch, the light bulb within the refrigerator remains on when the the door is closed. The power of the light bulb is ; assume that...

Homework Statement Ive got a question regarding a recent AP free response, http://www.collegeboard.com/prod_downloads/ap/students/physics/b_physics_b_frq_03.pdf Problem 5 is about a simple refrigerator, work is applied and heat is removed keeping temperature constant. My question is on...

Homework Statement Why is the kichen floor around a household refrigerator usually wamer than the floor in other parts of the kitchen? Homework Equations none The Attempt at a Solution I have seen the refigeration cycle. The places where heat is dissapated is the condenser and...

Homework Statement a) Assume that a Carnot cycle is used to achieve that 250kg of water at 0 degrees celsius is frozen into ice using an ideal refigerator The room temperature is 27 degrees. What is the minimum amount of work input to the refrigerator to achieve this? b)Assume the refigerator...

A Carnot refrigerator operating between -10.0 C and 40.0 C extracts heat from the cold reservoir at the rate 300 J/s. What are (a) the coefficient of performance of this refrigerator, (b) the rate at which work is done on the refrigerator and (c) the rate at which heat is exhausted to the hot...

Air conditioners operate on the same principle as refrigerators. Consider an air conditioner that has 7.00 kg of refrigerant flowing through its circuit each cycle. The refrigerant enters the evaporator coils in phase equilibrium, with 54.0% of its mass as liquid and the rest as vapor. It flows...

This is an experiment I have to do... Using a timer (or watch) and a thermometer, conduct the following experiment to determine the rate of heat gain of your refrigerator. First make sure that the door of the refrigerator is not opened for at least a few hours so that steady operating...

Alright, I'm stuck on a few problems with a physics brain teaser sheet. 1. Suppose you have a very small kitchen with a refrigerator. Can you cool off the kitchen by leaving the refreigerator door open? 2. Which bracing for a screen is strongest: two vertical bars, one horizontal bar...

I recently particpated in a thread that was closed out before I got the answer to what seemed to me a kind of paradox A permanent magnet attaches to the side of a refrigerator. IT won't stay there forever , but it will for a very long time. All that time gravity wants to pull the magnet...

Feasibility of a "Warm Refrigerator" I'm looking for some critical feedback on the feasibility of this concept. As far as I'm aware, the purpose of a refrigerator is to extend the shelf life of perishable food products by lowering the environmental temperature of the food, thus slowing the...

mmm.. just noticed that my other thread appear to not work for some reason.. anyhow, here is a resubmit: Problem: A heat engine is a decive that uses heat to perform work. the Carnot ideal heat engine runs through a cycle, which consists of a isothermal, adiabatic, again isothermal, and...

100 mL of water at 288 K is placed in the freezer compartment of a refrigerator with a coefficient of performance of 4.0. How much heat energy is exhausted into the room as the water is changed to ice at 258 K? (The answer is 5.34 x 10^4 J) I tried using the Brayton-cycle refrigerator to...

(1) A refrigerator with mass m is pushed up a ramp at constant speed by a man applying a force F . The ramp is at an angle \theta above the horizontal. Neglect friction for the refrigerator. If the force F is horizontal , calculate its magnitude in terms of m and \theta . Ok so I...

please somebody help me! Electrical refrigerator contains 242 gr.Freon(mm.121).For the evaporation of 1 mole of this freon we need 4,8kcal.the capacity of the refrigerator is 120 liters.The performance coefficient is 25%.To incease the temperature of one mole of air to 1 C degree we need 7...

A vessel containing 8.43 kg of water at 21.1C is put into a refrigerator. The 0.1655 hp motor runs for 9 min to cool the liquid to the refrigerator's low temperature 4C. What is the COP of the refrigerator? W=P(delta)t = 123.463Wx540s = 66670.02 J COP = Qc/W Please Help. Thank...

Suppose that you want to freeze 1 kg of water for a party, and only have 5 minutes to do it. Relying on nothing but your keen physical abilities, a dixie cup, duct tape and a piece of string, you manage to build a refrigerator unit which can do the job. The temperature inside the refrigeration...

OK someoone on a different forum said his refrigerator is an 80 watt refrigerator (small lil college fridge). As in it takes 80 watts from the wall. Isnt it true that this isn't the same amount of heat that can be taken out of the contents inside? I remember someone talking about an...

The question reads... A heat pump is a refrigerator that uses the inside of a building as a hot-temp reservoir in the winter and the outside of the building as a hot-temp reservoir in the summer. So... For a carnot refrigerator engine operating between 25C and 40C in the summer, what is the...

The question reads... A heat pump is essentially a refrigerator engine that uses the inside of a building as a hot reservoir in the winter and the outside of the building as the hot reservoir in the summer. A) For a carnot refrigerator engine operating between 25 C and 40 C in the summer, what...

I found an unopened bottle of Worcester sauce in the cabinet this morning. It expired over a year ago...and its the good stuff too. I once found a jar of mustard that expired over five years earlier. It's like that jar was evil so no one would ever use it. We continued to buy mustard as if...

1. In older houses, when a refrigerator starts up, the lights may dim briefly. When an electric heater is turned on, the lights may stay dimmed as long as it is on. Explain the difference. 2. Explain what is meant by the statement "a motor acts as a motor and generator at the same time." Can...

A refrigerator is approximately a uniform parallelepiped h = 7 ft tall, w = 3 ft wide, and d = 2 ft deep. It sits upright on a truck with its 3 ft dimension in the direction of travel. Assume that the refrigerator cannot slide on the truck and that its mass is 100 kg. For the first three parts...

They're coming to termite tent my apt. building Wednesday A.M. What the heck are those chemicals they use for this anyway? Anyone know? I think they will finish Thurs. afternoon and I'll be able start airing out the place Thursday night and move back in Friday evening. Anyone been through this...

Well I'm new, and I have a question :) I've been looking and searching lots of places, but no luck :( But my problem, which isn't really a problem, it's just something I would like to know :) I was wondering if there were a formula, that could find out how long time a glass of water or a...

This is just a common problem solving question, which I cannot make, I suspect because I'm bad at maths. Anyway, I want to see it done, hopefully to grasp it. I am doing physics, so, it's an exercise from one of my books. 18-11. Show that the efficiency e of a Carnot engine and the...

[SOLVED] Refrigerator Magnet?? A magnet is suppose to have two poles the north and south, it is said that you can't ever have a magnet with only one pole. So how do refrigerator magnets work if they only have one side?? Thanks, Daniel