What is the maximum power rating of a kettle

AI Thread Summary
The discussion centers on determining the maximum power rating of a kettle that can be used alongside a 750W microwave without exceeding the circuit's capacity. Participants analyze the total power consumption, which includes the microwave and additional loads from lights. The consensus is that the kettle's power rating must be calculated considering the existing load, which totals 1050W from the microwave and lights. The calculations suggest that the kettle's maximum power should not exceed 750W to avoid tripping the circuit. Overall, the key takeaway is that the kettle's power rating must be carefully balanced with the existing load to ensure safe operation.
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Hey, i got a circuit question, and I'm not sure if i did it right, and was wondering if anyone could show me how to do it

A 750W microwave oven is plugged into an outlet and turned on. All three lights are on. What is the maximum power rating of a kettle that could be operated in the other outlet without burning out the fuse.

a) 1.80 x 10^3W
b) 7.50 x 10^2W
c) 1.05 x 10^3W
d) 9.50 x 10^2W

What i did is, for each awnser i took the power reading and divided it by the total voltage, since P = IV P/V = I, i found out that the 1800W one produced a current of 15A and that was my awnser, but my other friends got 1500Wats as the
 

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Perhaps you need to consider the load presented by the microwave and the lightbulbs?
 
if we consider the bulbs then it be 300W + 750Wats added which is 1.05 x 10^3 but that doesn't equal the total power it can reach.
 
that's right, how much reserve power remains for the tea-kettle?
 
hmm Okay So i have 1050Wats/120V = 8.75 A so then 750/120 = 6.25 together they equal 15, so then would it be 750? but I'm not counting the inital current of 2.5A so I'm doing somethin wrong.
 
what initial current of 2.5 A? Everything adds up to 1800 Watts.
 
i don't think it is 1800wats, because that ALONE = 15A, and we still haven't included the 750W microwave + the 300Wats of lightbulbs
 
Pay attention!
EVERYTHING adds up to 1800 Watts.
1050 Watts already on, + 750 Watts kettle.
 
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