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प्रश्न
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उत्तर
We know that R = `"V"^2/"P"`
`"Resistance of 60 W-220 V bulb"/"Resistance of 60 W-220 V bulb" = (220)^2/60 x 60/(110)^2 = 4/1`
Thus, the required ratio is 4: 1.
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