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Question
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate the resistance of each heater.
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Solution

The resistance of each heater
Since P = `"V"^2/"R"`
or I = `"V"^2/"R" = (100 xx 100)/250 = 40 Omega`
Therefore, 40 Ω is the resistance of each heater.
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