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A family uses 8 kW of power. Direct sola...

A family uses 8 kW of power. Direct solar energy is incident on the horizontal surface at an average rate of 200W per sq. m. If 20% of this energy can be converted into useful electrical energy, how large an area is needed to supply 8 kW?

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20% of 200W = 40W/sq.m
Area required = `(8000)/(40)`sq.m = 200 sq.m.
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