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Question
An Electric bulb is marked 100 W, 230 V. What how long would this lamp take to consume one unit of electricity?
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Solution
Energy consumed in kWh = `("W" xx "Time in hour")/1000`
`= (100 xx "t"("in hr"))/1000`
If energy consumed in 1 kWh, then 1 = `(100 xx "t")/1000`
time required for consuming 1 kWh, t = 10 hour.
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