Heating Your Kitchen with Your Refrigerator

In summary, the question asks for the amount of time a 3.50 kW space heater would need to run in order to produce the same amount of heat in a kitchen as a refrigerator does when it freezes 1.46 kg of water into ice. After plugging in the given values and using the equations for heat, coefficient of performance and power, the calculated time was 56.45 seconds, but this was not the correct answer.
  • #1
2001
1
0

Homework Statement



How long would a 3.50 kW space heater have to run to put into a kitchen the same amount of heat as a refrigerator (coefficient of performance = 3.13) does when it freezes 1.46 kg of water at 21.4°C into ice at 0°C?

m=1.46 kg
c_water=4186 J/kg
Delta T= 21.4°C
L_fusion= 3.34x10^5 J/kg
COP= 3.13
P= 3.50 kW

Homework Equations



Q_c = m x c_water x Delta T + m x L_f

COP = Q_c/W

P = W/t

The Attempt at a Solution



I plugged everything into the equation for the heat and got 618427 J. Then I divided that by the coefficient of performance to get that work = 197581 J. Then, I divided that by 3500 W for the power and found that t = 56.45 s. And apparently that's not the answer. I'm not sure where I went wrong!
 
Physics news on Phys.org
  • #2
You computed the work done to transfer an amount of heat. Where did that heat go?
 

1. How does heating your kitchen with your refrigerator work?

Heating your kitchen with your refrigerator works through a process called heat exchange. The refrigerator's compressor compresses refrigerant gas, causing it to become hot. This hot gas then flows through coils located on the back of the fridge, releasing heat into the surrounding air. The cooled refrigerant then travels back into the fridge, where it absorbs heat from the interior of the fridge, keeping your food cold.

2. Is heating your kitchen with your refrigerator energy-efficient?

Yes, heating your kitchen with your refrigerator can be energy-efficient. By using the heat generated by the fridge's compressor, you are essentially recycling energy that would otherwise go to waste. This can help reduce your overall energy consumption and save you money on your utility bills.

3. Can heating your kitchen with your refrigerator affect the temperature inside the fridge?

Yes, heating your kitchen with your refrigerator can affect the temperature inside the fridge. As the fridge's compressor works harder to generate heat, it may have a harder time maintaining a consistent temperature inside the fridge. This can lead to fluctuations in temperature and potentially impact the freshness of your food.

4. Are there any safety concerns with heating your kitchen with your refrigerator?

Generally, there are no safety concerns with heating your kitchen with your refrigerator. However, it is important to make sure that the area around the fridge is free from any flammable materials and that there is enough space for proper ventilation. It is also important to regularly clean the coils on the back of the fridge to prevent any potential fire hazards.

5. Can heating your kitchen with your refrigerator be used as a primary heating source?

No, heating your kitchen with your refrigerator should not be used as a primary heating source. While it can provide some heat, it is not powerful enough to sufficiently heat a room. It is only meant to supplement your existing heating system and should not be relied upon as the main source of heat in your home.

Similar threads

I try to solve a thermodynamics problem on heat transfer
    • Introductory Physics Homework Help
Replies
3
Views
970
Optimizing Refrigerator Efficiency: Solving for Necessary Power Draw
    • Introductory Physics Homework Help
Replies
2
Views
3K
B Heat pump as a heat engine that operates in reverse
    • Thermodynamics
Replies
3
Views
557
Why use c_p and not c_v as specific heat - Thermodynamics
    • Introductory Physics Homework Help
Replies
2
Views
1K
Solving Heat Engine & Refrigerator Problems
    • Introductory Physics Homework Help
Replies
2
Views
2K
Physics Homework about using Electricity to Heat Flowing Water
    • Introductory Physics Homework Help
Replies
9
Views
883
Mass of Ice required to achieve a certain final Temperature
    • Introductory Physics Homework Help
Replies
3
Views
2K
Thermodynamics - Hypothermia - Heat loss
    • Introductory Physics Homework Help
Replies
12
Views
2K
Modeling a kongming lantern (sky lantern)
    • Introductory Physics Homework Help
Replies
6
Views
1K
Is the Thermal/Mechanics Problem incoherent?
    • Introductory Physics Homework Help
Replies
8
Views
936

Hot Threads

Recent Insights

Back
Top