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प्रश्न
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उत्तर
Given, P = 100 W, p.d. = 220 V
We know that,
P = `"V"^2/"R"`
P = `"V"^2/"R" = *(220)^2/100 = 484 Omega`
Also, we know that,
P=VI
I = `"P"/"V" = 100/220 = 0.45`A
Thus a fuse of rating 7A may be used with the appliance and it should be connected in the live wire before connectimg it to the appliance
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