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

AI Thread Summary
If the voltage supplied to a refrigerator rated at 80W and 250V drops to 50V, the resistance remains constant at 781.25 ohms. The current would decrease significantly from 0.32 A to 0.064 A, resulting in a power output of only 3.2 W. This reduction in power could lead to inadequate cooling and potential damage to the appliance, particularly if the compressor fails to operate properly. There is a risk of overheating if the compressor stalls and continues to draw current without functioning. Overall, the appliance may be at risk of damage under these conditions.
ritwik06
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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

******************************************

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.
 
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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.

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