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Question
An electrical appliance has a rating 100 W, 120V. The resistance of element of appliance when in use:
Options
1.2 Ω
144 Ω
120 Ω
100 Ω
Solution
144 Ω
Given , Power (P) = 100 W
Potential difference , V = 120 volt
∴ Resistance , R = `("V"^2)/"P" = (120)^2/100 = 144 Ω`
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