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For how many hours can a 100 W bulb be ...

For how many hours can a 100 W bulb be used to have one unit of electrical energy consumption ?

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When used for identical time, a 100 W bulb consumers only `(1)/(10^(th))`of the energy consumed by a 1000 W bulb. For equal consumption of electrical energy, a 100 W bulb is used for a time that is 10 times the time a 1000 W bulb is used. If a 1000 W bulb consumes one unit of electrical energy when used for one hour, then a 100 W bulb consumes the same one unit of electrical energy if it is used for 10 hours.
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