Effects of Voltage Drop on a Refrigerator Rated 80W & 250V

[ritwik06]

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 resistance to be constant.
--------------------------------------------------------
Current earlier=P/V
=80/250
=0.32 A
----------------------------------------------------

Current when voltage falls to 50V

=50/781.25 (V=IR)
=0.064 A

---------------------------------------------------

Power will also decrease.
P=VI
=50*0.064
=3.2 W

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It seems that the appliance will be damaged. I have no idea about anything further. Am I right? I have written everything i could make out. Please help me now.

 

[chroot]

Your reasoning looks entirely correct to me. Of course, in the real world, you're probably right -- the appliance may well be damaged if its compressor can't turn and it just sits there soaking up stall current until it overheats.

- Warren

 

[Moetasim]

I would like to clarify that the effects of voltage drop on a refrigerator rated 80W and 250V will depend on the type of refrigerator and its specific design. It is important to note that voltage drop can occur due to various factors such as long wiring, poor connections, and high demand on the electrical grid. In this scenario, assuming the refrigerator is designed to operate at 250V, a decrease in voltage to 50V will result in a decrease in power consumption as calculated in the attempt at a solution. This means that the refrigerator will not operate at its full capacity and may take longer to cool or maintain its temperature.

However, it is unlikely that the appliance will be damaged as most modern refrigerators have built-in protection mechanisms to prevent damage from voltage fluctuations. These mechanisms can include voltage stabilizers or surge protectors. In addition, the refrigerator's internal components such as the compressor and fan motor are designed to operate within a certain voltage range to ensure their longevity.

In summary, a voltage drop to 50V may affect the performance of the refrigerator, but it is unlikely to cause any significant damage. It is important to address the root cause of the voltage drop to ensure the safe and efficient operation of the appliance.