Determining the Resistance of an Electric Blanket

AI Thread Summary
The discussion revolves around calculating the resistance of an electric blanket that consumes 50 watts of power at a voltage of 240 volts. The user attempts to find resistance using the formula R = V/I, leading to the calculation of current as I = 50/240, resulting in approximately 0.208 A. This yields a resistance of R = 240/0.208, which equals about 1152 ohms. The user expresses confusion over the high resistance value compared to previous problems involving much lower resistance figures. Ultimately, the calculations are confirmed as correct, clarifying that higher resistance values are typical for appliances like electric blankets.
Johny Prime
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Homework Statement


A typical electric blanket consumes 50 W of power when operating. What is the overall resistance of the blanket if it is designed to be plugged into a standard powerpoint?
Power = 50 watts
Voltage = 240 v (standard powerpoint)

Homework Equations


I (current) = Voltage/ Resistance
Power = V x I

The Attempt at a Solution


So we are trying to find the overall resistance:
R = V/I
R = 240/I
P/V = I ?
50/240 = I ?
I = 0.2083333 (I don't think that looks right)
So then, R= 240/0.2083333
R= 1152??
Resistance is 1152 ohms?
These answers seem very strange to me and I am uncertain as to whether my logic is sound or not.
If my logic is incorrect, could someone inform me of the logic of the correct way? Thanks!
 
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It is correct.
Why does it seem strange to you?
 
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mfb said:
It is correct.
Why does it seem strange to you?
I wasn't sure because all the questions I had done before this had very small resistance (like 6), and I wasn't sure what an actual appliance might have in terms of resistance. Thanks for the confirmation!
 
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